Supplemental Prospectus (Form 424B5)

Filed Pursuant to Rule 424(b)(5)
Registration No. 333-282711

PROSPECTUS SUPPLEMENT

(To Prospectus dated October 18, 2024)

$185,000,000

6.375% Fixed-to-Floating Rate Subordinated Notes due 2035

We are offering $185,000,000 aggregate principal amount of 6.375% fixed-to-floating rate subordinated notes due 2035 (the "Notes") pursuant to this prospectus supplement and the accompanying prospectus. The Notes will be offered in minimum denominations of $1,000 and integral multiples of $1,000 in excess thereof. The Notes will mature on November 15, 2035 (the "Maturity Date"). From and including the date of original issuance to, but excluding, November 15, 2030 or the date of earlier redemption (the "fixed rate period"), the Notes will bear interest at an initial rate of 6.375% per annum, payable semi-annually in arrears on May 15 and November 15 of each year, commencing on May 15, 2026. The last interest payment date for the fixed rate period will be November 15, 2030. From and including November 15, 2030 to, but excluding, the Maturity Date or the date of earlier redemption (the "floating rate period"), the Notes will bear interest at a floating rate per annum equal to the Benchmark rate (which is expected to be Three-Month Term SOFR), each as defined and subject to the provisions described under "Description of the Notes- General" in this prospectus supplement, plus 307.5 basis points, payable quarterly in arrears on February 15, May 15, August 15 and November 15 of each year, commencing on February 15, 2031. Notwithstanding the foregoing, if the Benchmark rate is less than zero, the Benchmark rate will be deemed to be zero.

We may, at our option, beginning with the interest payment date of November 15, 2030 and on any interest payment date thereafter, redeem the Notes, in whole or in part. In addition, we may, at our option, redeem the Notes prior to maturity, in whole but not in part, upon or after the occurrence of a "Tier 2 Capital Event" or a "Tax Event" (each as defined under "Description of Notes" in this prospectus supplement) or our being required to register as an investment company under the Investment Company Act of 1940, as amended (the "1940 Act"). The Notes will not otherwise be redeemable by us prior to maturity, unless certain events occur, as described under "Description of the Notes-Redemption" in this prospectus supplement. The redemption price for any redemption is 100% of the principal amount of the Notes being redeemed, plus accrued and unpaid interest thereon to, but excluding, the date of redemption. Any redemption of the Notes will be subject to the receipt of the approval of the Board of Governors of the Federal Reserve System (the "Federal Reserve") to the extent then required under applicable laws or regulations, including capital regulations.

The Notes will be unsecured subordinated obligations, will rank pari passu, or equally, with all of our existing and future unsecured subordinated debt, will be senior to all of our existing and future junior subordinated debt and will be junior to all of our existing and future senior debt. The Notes will be structurally subordinated to all existing and future liabilities of our subsidiaries and will be effectively subordinated to our existing and future secured indebtedness, to the extent of the value of the collateral securing such indebtedness. There will be no sinking fund for the Notes. The Notes will be obligations of OceanFirst Financial Corp. ("OceanFirst" or the "Company") only and will not be obligations of, and will not be guaranteed by, any of OceanFirst's subsidiaries. For a more detailed description of the Notes, see "Description of the Notes."

Prior to this offering, there has been no public market for the Notes. The Notes will not be listed on any securities exchange or included in any automated quotation system.

The Notes are not deposits and are not insured by the Federal Deposit Insurance Corporation (the "FDIC") or any other governmental agency. The Notes are ineligible as collateral for a loan or extension of credit from OceanFirst or any of its subsidiaries. None of the U.S. Securities and Exchange Commission (the "SEC"), the FDIC, the Federal Reserve, the Office of the Comptroller of the Currency (the "OCC") or any other bank regulatory agency or any state securities commission has approved or disapproved of the Notes or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

Investing in the Notes involves risks. See "Risk Factors" beginning on page S-12 of this prospectus supplement and those risk factors in the documents incorporated by reference in this prospectus supplement and the accompanying prospectus.

The underwriters expect to deliver the Notes to purchasers in book-entry form through the facilities of The Depository Trust Company, against payment on or about October 29, 2025. See "Underwriting" in this prospectus supplement for details.

Joint Book-running Managers

The date of this prospectus supplement is October 27, 2025.

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

PROSPECTUS

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ABOUT THIS PROSPECTUS SUPPLEMENT

Unless the context indicates otherwise, the terms "OceanFirst," the "Company," "we," "our" and "us" in this prospectus supplement and the accompanying prospectus refer to OceanFirst Financial Corp. and its subsidiaries.

References to the "Bank" refer to OceanFirst Bank, National Association. References to a particular year mean our fiscal year commencing on January 1 and ending on December 31 of that year.

This prospectus supplement and the accompanying prospectus are part of a shelf registration statement on Form S-3 that we filed with the SEC. The registration statement incorporates by reference important business and financial information about us that is not included in or delivered with this document. This information, other than exhibits to documents that are not specifically incorporated by reference into this prospectus supplement or the accompanying prospectus, is available to you via the SEC's website at www.sec.gov or without charge upon written or oral request to OceanFirst at the address or telephone number indicated in the section entitled "Incorporation of Certain Documents by Reference" in this prospectus supplement.

This document contains two parts. The first part is this prospectus supplement, which contains specific information about us and the terms on which we are selling the Notes and adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein. The second part is the accompanying prospectus dated October 18, 2024, which contains and incorporates by reference a more general description of the securities we may offer from time to time, some of which does not apply to the Notes we are offering, and important business and financial information about us. If information contained in this prospectus supplement differs or varies from the information contained in the accompanying prospectus, you should rely on the information set forth in this prospectus supplement. If information contained in any document having a later date than this prospectus supplement (for example, a document incorporated by reference in the accompanying prospectus) differs or varies from the information contained in this prospectus supplement or the accompanying prospectus, the statement in the document having the later date modifies or supersedes the earlier statement.

Neither we nor the underwriters have authorized anyone to provide you with any information other than that contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any "free writing prospectus" prepared by or on behalf of us or to which we may have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not, and the underwriters are not, making an offer to sell the Notes in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, any free writing prospectus relating to this prospectus supplement provided or approved by us and the documents incorporated by reference in either this prospectus supplement or the accompanying prospectus is accurate only as of the respective dates of those documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

Before you invest in the Notes, you should carefully read the registration statement (including the exhibits thereto) of which this prospectus supplement and the accompanying prospectus form a part, this prospectus supplement, the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The documents incorporated by reference into this prospectus supplement are described under "Incorporation of Certain Documents by Reference."

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our reports filed electronically with the SEC are available to the public over the Internet at the SEC's website at www.sec.gov.

We also maintain an Internet site where you can find additional information about us, including our SEC filings. The address of our Internet site https://ir.oceanfirst.com. All Internet addresses provided in this prospectus supplement or in the accompanying prospectus are for informational purposes only and are not intended to be hyperlinks. In addition, the information on our Internet website, or any other Internet site described in this prospectus supplement or in the accompanying prospectus, is not a part of, and is not incorporated or deemed to be incorporated by reference in, this prospectus supplement or in the accompanying prospectus or other offering materials.

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INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to "incorporate by reference" much of the information that we file with it, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference is an important part of this prospectus supplement and the accompanying prospectus. Any statement contained in a document incorporated or deemed to be incorporated by reference into this prospectus supplement or the accompanying prospectus will be deemed to be modified or superseded for purposes of this prospectus supplement or the accompanying prospectus to the extent that a statement contained in this prospectus supplement or the accompanying prospectus or any other subsequently filed document that is deemed to be incorporated by reference into this prospectus supplement or the accompanying prospectus modifies or supersedes the statement. In other words, in the case of a conflict or inconsistency between information contained in this prospectus supplement and the accompanying prospectus and information incorporated by reference into this prospectus, you should rely on the information contained in the document that was filed later. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this prospectus supplement or the accompanying prospectus.

This prospectus supplement and the accompanying prospectus incorporate by reference the documents listed below and all documents we subsequently file with the SEC pursuant to Sections 13(a), 13(c), 14, or 15(d) of the Exchange Act, prior to the termination of the offering of the Notes described in this prospectus supplement; provided, however, that we are not incorporating by reference any documents, portions of documents or other information deemed to have been "furnished" and not "filed" with the SEC:

Upon request, we will provide to each person, including any beneficial owner, to whom a copy of this prospectus supplement is delivered, a copy of any or all of the information that has been incorporated by reference in this prospectus supplement but not delivered with this prospectus supplement (other than the exhibits to such documents which are not specifically incorporated by reference therein). We will provide this information at no cost to the requester upon written or oral request to OceanFirst Financial Corp., Attn: Investor Relations, 110 West Front Street, Red Bank, New Jersey 07701; Tel.: (732) 240-4500.

You should rely only on the information incorporated by reference or set forth in this prospectus supplement and the accompanying prospectus or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. Neither we nor any underwriters, dealers or agents have authorized anyone else to provide you with additional or different information.

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CAUTIONARY NOTE CONCERNING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus and the documents incorporated by reference or deemed incorporated by reference into this prospectus supplement or the accompanying prospectus and any other written or oral statements made by us from time to time may contain forward-looking statements within the meaning of the federal securities laws. Words such as "expects," "believes," "should," "plans," "anticipates," "will," "potential," "could," "intend," "may," "outlook," "predict," "project," "would," "estimated," "assumes," "likely," and variations of such similar expressions are intended to identify such forward-looking statements.

All forward-looking statements are subject to risks, uncertainties and other factors, many of which are beyond our control, that may cause the actual results, performance or achievements of OceanFirst to differ materially from any results expressed or implied by such forward-looking statements. Such factors include, but are not limited to: changes in interest rates, inflation, general economic conditions, including potential recessionary conditions, levels of unemployment in the Company's lending area, real estate market values in the Company's lending area, potential goodwill impairment, natural disasters, potential increases to flood insurance premiums, the current or anticipated impact of military conflict, terrorism or other geopolitical events, the imposition of tariffs or other domestic or international governmental policies and retaliatory responses, the level of prepayments on loans and mortgage-backed securities, legislative/regulatory changes, monetary and fiscal policies of the U.S. Government, including policies of the U.S. Treasury and the Board of Governors of the Federal Reserve System, the quality or composition of the loan or investment portfolios, demand for loan products, deposit flows, the availability of low-cost funding, changes in liquidity, including the size and composition of the Company's deposit portfolio and the percentage of uninsured deposits in the portfolio, changes in capital management and balance sheet strategies and the ability to successfully implement such strategies, competition, demand for financial services in the Company's market area, changes in investor sentiment and consumer spending, borrowing and saving habits, changes in accounting principles, a failure in or breach of the Company's operational or security systems or infrastructure, including cyberattacks, the failure to maintain current technologies, failure to retain or attract employees, the impact of pandemics on our operations and financial results and those of our customers and the Bank's ability to successfully integrate acquired operations.

These and other factors are more fully described under "Risk Factors" below and in Item 1A of our most recent Annual Report on Form 10-K for the fiscal year ended December 31, 2024, filed with the SEC on February 28, 2025, and other factors discussed in the filings we make with the SEC under the Exchange Act.

All forward-looking statements attributable to our Company are expressly qualified in their entirety by these cautionary statements. Forward-looking statements speak only as of the date on which such statements are made. Except as required by law, we disclaim any obligation to update these forward-looking statements, whether as a result of new information, future events or otherwise. There is no assurance that future results, levels of activity, performance or goals will be achieved.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information from this prospectus supplement and does not contain all of the information that you should consider in making your investment decision. You should read this summary together with the more detailed information appearing elsewhere in this prospectus supplement, as well as the information in the accompanying prospectus and in the documents incorporated by reference or deemed incorporated by reference into this prospectus supplement and the accompanying prospectus. You should carefully consider, among other things, the matters discussed in the section titled "Risk Factors" in this prospectus supplement, in our most recent Annual Report on Form 10-K for the year ended December 31, 2024, in our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025 and June 30, 2025, and in other documents that we subsequently file with the SEC. In addition, certain statements include forward-looking information that involves risks and uncertainties. See "Cautionary Note Concerning Forward-Looking Statements" in this prospectus supplement.

Overview

OceanFirst Financial Corp. is incorporated under Delaware law and serves as the holding company for OceanFirst Bank N.A. At June 30, 2025, the Company had consolidated total assets of $13.3 billion and total stockholders' equity of $1.6 billion. The Company is subject to regulation by the Federal Reserve and the Securities and Exchange Commission (the "SEC"). The Bank is primarily subject to regulation and supervision by the OCC, as well as the Consumer Financial Protection Bureau (the "CFPB") due to the Bank having in excess of $10 billion in assets. The Bank is also subject to regulation and supervision by the FDIC, as the deposit insurer. Currently, the Company transacts the vast majority of its business through the Bank, its wholly owned subsidiary.

The Bank's principal business is originating commercial real estate and other commercial loans. The Bank also invests in other types of loans, including residential construction and consumer loans. The Bank primarily funds these loans by attracting retail and commercial deposits. In addition, the Bank invests in mortgage-backed securities, securities issued by the U.S. Government and agencies thereof, corporate securities and other investments permitted by applicable law and regulations. The Bank's revenues are derived principally from interest on its loans, and to a lesser extent, earnings on its debt and equity securities. The Bank also receives income from other products and services it offers including bankcard services, trust and fiduciary services, deposit account services, and commercial loan swap income. The Bank's primary sources of funds are deposits, principal and interest payments on loans and investments, Federal Home Loan Bank ("FHLB") advances, and other borrowings. While scheduled payments on loans and securities are predictable sources of funds, deposit flows, loan prepayments, and loan and investment activity are greatly influenced by changes in market interest rates, competition, general economic conditions, including levels of unemployment and real estate values, and inflation.

Our common stock is listed on the Nasdaq Global Select Market under the symbol "OCFC." Our depositary shares are listed on the Nasdaq Global Select Market under the symbol "OCFCP."

Corporate Information

Our principal executive office is located at 110 West Front Street, Red Bank, New Jersey 07701 and our telephone number is (732) 240-4500. We maintain a website at www.oceanfirst.com. The information on our website is not part of this prospectus supplement or the accompanying prospectus and is not incorporated by reference herein or therein.

Recent Developments

The tables below present highlights of our unaudited preliminary financial results as of and for the periods indicated. These unaudited preliminary financial results have been prepared by, and are the responsibility of, our

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management. Our Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 will include our unaudited financial statements for the three and nine months ended September 30, 2025, including the footnote disclosures associated with our results, as well as management's discussion and analysis of financial condition and results of operations.

Our unaudited financial statements for the three and nine months ended September 30, 2025 will not be available until after this offering is completed and, consequently, will not be available to you before your investment decision with respect to this offering. Preparation of our Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 could result in changes to the unaudited preliminary financial results presented below.

The following should be read in conjunction with (i) our consolidated financial statements and related notes, as well as management's discussion and analysis of financial condition and results of operations, in our 2024 10-K and our other filings with the SEC that are incorporated by reference herein and (ii) the "Cautionary Note Concerning Forward-Looking Statements" and "Risk Factors" in this prospectus supplement and similar sections in our filings with the SEC that are incorporated by reference herein.

Neither the Company's independent accountants, nor any other independent accountants, have compiled, examined, or performed any procedures with respect to the preliminary financial information contained herein, nor have they expressed any opinion or any other form of assurance on such information, and assume no responsibility for, and disclaim any association with, the preliminary financial information.

Selected Condensed Consolidated Statements of Income Data

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Selected Consolidated Statements of Financial Condition Data

The Company's Board of Directors declared its 115th consecutive quarterly cash dividend on common stock. The quarterly cash dividend on common stock of $0.20 per share will be paid on November 14, 2025 to common stockholders of record on November 3, 2025.

During the quarter ended September 30, 2025, the Company made the strategic decision to outsource its residential lending origination and title business, which impacted the quarter's results. The Company recognized $4.1 million of restructuring charges during the quarter, and will incur approximately $8 million of additional charges in the fourth quarter of 2025. The residential outsourcing initiative will result in an 11% work reduction and anticipated annual expense savings of $14 million offset in part by a reduction in gain on sale of loans starting in 2026.

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THE OFFERING

The following summary highlights selected information from this prospectus supplement and the accompanying prospectus about the Notes and this offering. This description is not complete and does not contain all of the information that you should consider before investing in the Notes. You should read this prospectus supplement and the accompanying prospectus, as well as the documents incorporated by reference herein and therein, carefully before making a decision about whether to invest in the Notes. For a more complete understanding of the Notes, you should read the section of this prospectus supplement entitled "Description of the Notes."

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RISK FACTORS

An investment in our securities is subject to risks inherent to our business. Before making an investment decision, you should carefully consider the risks and uncertainties described below together with the risk factors and other information included in our Annual Report on Form 10-K for the year ended December 31, 2024, as supplemented by our Current Reports on Form 8-K, our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025 and June 30, 2025, and in other documents that we subsequently file with the SEC, all of which are incorporated by reference into this prospectus supplement and the accompanying prospectus. Additional risks and uncertainties that management is not aware of or that management currently deems immaterial may also impair our business operations. See also the discussion under the heading "Cautionary Note Concerning Forward-Looking Statements." This prospectus supplement and the accompanying prospectus are qualified in their entirety by these risk factors. If any of these risks actually occurs, our financial condition and results of operations could be materially and adversely affected. If this were to happen, the value of our securities could decline significantly, and you could lose all or part of your investment.

Risk Factors Related to the Notes

The Notes will be unsecured and subordinated to any existing and future Senior Indebtedness.

The Notes will be subordinated obligations of OceanFirst. Accordingly, they will be junior in right of payment to any existing and all future Senior Indebtedness, and in certain events of insolvency, to other financial obligations as described under "Description of the Notes." Our Senior Indebtedness includes all indebtedness, except indebtedness that is expressly subordinated to or ranked pari passu with the Notes, subject to certain exceptions. The Notes will rank equally with all other unsecured subordinated indebtedness of OceanFirst issued in the future under the Indenture. In addition, the Notes will be structurally subordinated to all existing and future indebtedness, liabilities and other obligations, including deposits of our subsidiaries, including the Bank. As of June 30, 2025, on a consolidated basis, our outstanding debt and deposits totaled approximately $11.4 billion, which includes approximately $10.2 billion of deposit liabilities that would rank senior to the Notes. In addition, as of June 30, 2025, we (at the holding company level) had no indebtedness that would rank senior to the Notes, $125.0 million of indebtedness that would rank pari passu to the Notes, and $82.5 million aggregate principal amount of our fixed/floating rate junior subordinated deferrable interest debentures that would rank junior to the Notes.

In addition, the Notes will not be secured by any of our assets. As a result, the Notes will be effectively subordinated to all of our secured indebtedness to the extent of the value of the assets securing such indebtedness. The Indenture governing the Notes does not limit the amount of Senior Indebtedness and other financial obligations or secured obligations that we or our subsidiaries may incur.

As a result of the subordination provisions described above, holders of the Notes may not be fully repaid in the event of our bankruptcy, liquidation or reorganization.

The Notes will not be insured or guaranteed by the FDIC, any other governmental agency or any of our subsidiaries. The Notes will be structurally subordinated to the indebtedness and other liabilities of our subsidiaries, which means that creditors of our subsidiaries generally will be paid from those subsidiaries' assets before holders of the Notes would have any claims to those assets.

The Notes are not savings accounts, deposits or other obligations of the Bank or any of our non-bank subsidiaries and are not insured or guaranteed by the FDIC or any other governmental agency or public or private insurer. The Notes are obligations of OceanFirst only and are neither obligations of, nor guaranteed by, any of our subsidiaries. The Notes will be structurally subordinated to all existing and future indebtedness and other liabilities of our subsidiaries, which means that creditors of our subsidiaries (including, in the case of the Bank, its depositors) generally will be paid from those subsidiaries' assets before holders of the Notes would have any

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claims to those assets. Even if we become a creditor of any of our subsidiaries, our rights as a creditor would be subordinate to any security interest in the assets of that subsidiary and any debt of that subsidiary senior to that held by us, and our rights could otherwise be subordinated to the rights of other creditors and depositors of that subsidiary. Furthermore, none of our subsidiaries is under any obligation to make payments to us, and any payments to us depend on the earnings or financial condition of our subsidiaries and various business considerations. Statutory, contractual or other restrictions also limit our subsidiaries' ability to pay dividends or make distributions, loans or advances to us. For these reasons, we may not have access to any assets or cash flows of our subsidiaries to make interest and principal payments on the Notes.

The Indenture governing the Notes does not contain any limitations on our ability to incur additional indebtedness, grant or incur a lien on our assets, sell or otherwise dispose of assets, pay dividends or repurchase our capital stock.

Neither we nor any of our subsidiaries are restricted from incurring additional indebtedness or other liabilities, including additional senior or subordinated indebtedness, under the Indenture governing the terms of the Notes. If we incur additional indebtedness or liabilities, our ability to pay our obligations on the Notes could be adversely affected. We expect that we will from time to time incur additional indebtedness and other liabilities. In addition, we are not restricted under the Indenture governing the Notes from granting or incurring a lien on any of our assets, selling or otherwise disposing of any of our assets, paying dividends or issuing or repurchasing our securities including our regular quarterly dividend and share repurchases pursuant to our previously announced share repurchase program.

In addition, there are no financial covenants in the Indenture governing the Notes. Except as expressly provided in the Indenture, you are not protected under the Indenture governing the Notes in the event of a highly leveraged transaction, reorganization, default under our existing indebtedness, restructuring, merger or similar transaction that may adversely affect you. See "Description of the Notes - Consolidation, Merger, Sale of Assets and Other Transactions."

Payments on the Notes will depend on receipt of dividends and distributions from our subsidiaries.

We are a bank holding company and we conduct substantially all of our operations through subsidiaries, including the Bank. We depend on dividends, distributions and other payments from our subsidiaries to meet our obligations, including to fund payments on the Notes.

Federal and state banking regulations limit dividends from our bank subsidiary to us. Generally, banks are prohibited from paying dividends when doing so would cause them to fall below regulatory minimum capital levels. Additionally, limits exist on banks paying dividends in excess of net income for specified periods. The total amount available for payment of dividends by the Bank was approximately $18.6 million at June 30, 2025, based on the Bank's retained net income for six months ended June 30, 2025 and the two prior years. If this amount had been fully distributed as of June 30, 2025, the Bank would have maintained enough capital to be considered well-capitalized at that date. During the six months ended June 30, 2025 and the year ended December 31, 2024, the Bank paid dividends of $62.0 million and $85.3 million, respectively, to us. In addition, federal bank regulatory agencies have the authority to prohibit the Bank from engaging in unsafe or unsound practices in conducting its business. The payment of dividends or other transfers of funds to us, depending on the financial condition of the Bank, could be deemed an unsafe or unsound practice.

Dividend payments from the Bank would also be prohibited under the "prompt corrective action" regulations of federal bank regulators if the Bank is, or after payment of such dividends would be, undercapitalized under such regulations. In addition, the Bank is subject to restrictions under federal law that limit its ability to transfer funds or other items of value to us and our non-bank subsidiaries, including affiliates, whether in the form of loans and other extensions of credit, investments and asset purchases, or as other transactions involving the transfer of value. Unless an exemption applies, these transactions by the Bank with us

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are limited to 10% of the Bank's capital stock and surplus and, with respect to all such transactions with affiliates in the aggregate, to 20% of the Bank's capital stock and surplus. Moreover, loans and extensions of credit by the Bank to its affiliates, including us, generally are required to be secured in specified amounts. A bank's transactions with its non-bank affiliates also are required generally to be on arm's-length terms.

Accordingly, we can provide no assurance that we will receive dividends or other distributions from our bank subsidiary and our other subsidiaries in an amount sufficient to pay interest on or principal of the Notes.

Our indebtedness could adversely affect our financial results and prevent us from fulfilling our obligations under the Notes.

In addition to our currently outstanding indebtedness and any additional indebtedness we may incur pursuant to this offering, we may be able to borrow substantial additional indebtedness, including Senior Indebtedness, in the future. If new indebtedness is incurred in addition to our current debt levels, the related risks that we now face could increase.

Our indebtedness, including the indebtedness we may incur in the future, could have important consequences for the holders of the Notes, including:

The Indenture does not limit the incurrence of additional indebtedness by us, including secured indebtedness, which would be effectively senior to the Notes to the extent of the value of the collateral securing such indebtedness.

We may not be able to generate sufficient cash to service all of our debt, including the Notes.

Our ability to make scheduled payments of principal and interest, or to satisfy our obligations in respect of our debt or to refinance our debt, will depend on the future performance of our operating subsidiaries. Prevailing economic conditions (including interest rates), regulatory constraints, including, without limitation, limiting distributions to us from the Bank and required capital levels with respect to the Bank and financial, business and other factors, many of which are beyond our control, will also affect our ability to meet these needs. Our subsidiaries may not be able to generate sufficient cash flows from operations, or we may be unable to obtain future borrowings in an amount sufficient to enable us to pay our debt, or to fund our other liquidity needs. We may need to refinance all or a portion of our debt at or before maturity. We may not be able to refinance any of our debt when needed (including, without limitation, upon commencement of the floating rate period) on commercially reasonable terms or at all.

Regulatory guidelines may restrict our ability to pay the principal of, and accrued and unpaid interest on, the Notes.

As a bank holding company, our ability to pay the principal of, and interest on, the Notes is subject to the rules and guidelines of the Federal Reserve regarding capital adequacy. We intend to treat the Notes as "Tier 2

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capital" under these rules and guidelines. The Federal Reserve guidelines generally require us to review the effects of the cash payment on Tier 2 capital instruments, such as the Notes, on our overall financial condition. The guidelines also require that we review our net income for the current and past four quarters, and the amounts we have paid on Tier 2 capital instruments for those periods, as well as our projected rate of earnings retention. Moreover, pursuant to federal law and Federal Reserve regulations, as a bank holding company, we are required to act as a source of financial and managerial strength to the Bank and commit resources to its support, including, without limitation, the guarantee of its capital plans if it is undercapitalized. Such support may be required at times when we may not otherwise be inclined or able to provide it. As a result of the foregoing, we may be unable to pay accrued interest on the Notes on one or more of the scheduled interest payment dates, or at any other time, or the principal of the Notes at the maturity of the Notes.

If we were to be the subject of a bankruptcy proceeding under Chapter 11 of the U.S. Bankruptcy Code, then the bankruptcy trustee would be deemed to have assumed, and would be required to cure immediately, any deficit under any commitment we have to any of the federal banking agencies to maintain the capital of the Bank, and any other insured depository institution for which we have such a responsibility, and any claim for breach of such obligation would generally have priority over most other unsecured claims.

Holders of the Notes will have limited rights, including limited rights of acceleration, if there is an event of default.

Payment of principal on the Notes may be accelerated only in the case of certain events of bankruptcy or insolvency involving us or the Bank. There is no automatic acceleration, or right of acceleration, in the case of default in the payment of principal of or interest on the Notes, or in the performance of any of our other obligations under the Notes or the Indenture governing the Notes. Our regulators can, if we or the Bank become subject to an enforcement action, prohibit the Bank from paying dividends to us, and prevent our payment of interest on or principal of the Notes and any dividends on our capital stock, but such limits will not permit acceleration of the Notes. See "Description of the Notes - Events of Default."

An active trading market for the Notes may not develop.

The Notes constitute a new issue of securities for which there is no existing trading market. We do not intend to apply for listing of the Notes on any securities exchange or for quotation of the Notes in any automated dealer quotation system. We cannot provide you with any assurance regarding whether a trading market for the Notes will develop, the ability of holders of the Notes to sell their Notes or the prices at which holders may be able to sell their Notes. The underwriters have advised us that they currently intend to make a secondary market in the Notes. The underwriters, however, are not obligated to do so, and any market-making with respect to the Notes may be discontinued at any time without notice. There may be a limited number of buyers if you decide to sell your Notes. This may affect the price you receive for your Notes or your ability to sell your Notes at all. Investors in the Notes may not be able to sell the Notes at all or may not be able to sell the Notes at prices that will provide them with a yield comparable to similar investments that have a developed secondary market, and may consequently suffer from increased pricing volatility and market risk.

If a trading market for the Notes develops, changes in the debt markets, among others, could adversely affect your ability to liquidate your investment in the Notes and the market price of the Notes.

Many factors could affect the trading market for, and the trading value of, the Notes. These factors include: the method of calculating the principal, premium, if any, interest or other amounts payable, if any, on the Notes; the time remaining to the maturity of the Notes; the ranking of the Notes; the redemption features of the Notes; the outstanding amount of subordinated notes with terms similar or identical to the Notes offered hereby; the prevailing interest rates being paid by other companies similar to us; changes in U.S. interest rates; whether the ratings on the Notes or us provided by any rating agency have changed; our financial condition, financial performance and future prospects; the level, direction and volatility of market interest rates generally; general

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economic conditions of the capital markets in the United States; and geopolitical conditions and other financial, political, regulatory, and judicial events that affect the capital markets generally. The condition of the financial markets and prevailing interest rates have fluctuated significantly in the past and are likely to fluctuate in the future. Such fluctuations could adversely affect the trading market (if any) for, and the market price of, the Notes.

Because the Notes may be redeemed at our option under certain circumstances prior to their maturity, if we elect to redeem all or any portion of the Notes, you may be subject to reinvestment risk.

On or after November 15, 2030, we may, at our option, redeem the Notes in whole or in part on each interest payment date. In addition, we may also redeem the Notes prior to maturity, at our option, in whole but not in part, upon or after the occurrence of (i) a Tier 2 Capital Event, (ii) a Tax Event or (3) our being required to register as an investment company under the Investment Company Act of 1940, as amended. The redemption price for any redemption is 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest thereon, if any, to, but excluding, the date of redemption. Any redemption of the Notes will be subject to the receipt of the approval of the Federal Reserve, to the extent then required under applicable laws or regulations, including capital regulations. Any such redemption may have the effect of reducing the income or return that you may receive on an investment in the Notes by reducing the term of the investment. Under current regulatory capital guidelines, the aggregate principal amount of the Notes that will count as Tier 2 capital will be reduced by 20% in each of the last five years prior to the Maturity Date of the Notes. As a result, we may be more likely to redeem the Notes prior to their Maturity Date. If this occurs, you may not be able to reinvest the proceeds at an interest rate comparable to the rate paid on the Notes. See "Description of the Notes - Redemption."

We may elect to redeem the Notes on or after the date on which they become redeemable at our option; however, investors should not expect us to make such election on such date when the Notes are first redeemable or at any time thereafter. Under Federal Reserve regulations, unless the Federal Reserve authorizes us in writing to do otherwise, we may not redeem the Notes unless they are replaced with other Tier 2 capital instruments or unless we can demonstrate to the satisfaction of the Federal Reserve that, following redemption, we will continue to hold capital commensurate with our risk.

The amount of interest payable on the Notes will vary after November 15, 2030.

During the fixed rate period, the Notes will bear interest at an initial rate of 6.375% per annum. Thereafter, the Notes will bear interest at a floating rate per annum equal to the Benchmark rate (which is expected to be Three-Month Term SOFR) plus 307.5 basis points, subject to the provisions under "Description of the Notes - Interest." The per annum interest rate that is determined at the reference time for each interest period will apply to the entire quarterly interest period following such determination date even if the Benchmark rate increases during that period.

Floating rate notes bear additional significant risks not associated with fixed rate debt securities. These risks include fluctuation of the interest rates and the possibility that you will receive an amount of interest that is lower than expected. We have no control over a number of matters, including, without limitation, economic, financial, and political events, that are important in determining the existence, magnitude, and longevity of market volatility and other risks and their impact on the value of, or payments made on, the Notes. In recent years, interest rates have been volatile, and that volatility may be expected in the future.

Our published credit ratings may not reflect all risks of an investment in the Notes.

The published credit ratings of us or our indebtedness are an assessment by rating agencies of our ability to pay our debts when due. These ratings are not recommendations to purchase, hold or sell the Notes, inasmuch as the ratings do not comment as to market price or suitability for a particular investor, are limited in scope, and do not address all material risks relating to an investment in the Notes, but rather reflect only the view of each rating

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agency at the time the rating is issued. The published credit ratings assigned to the Notes may not reflect the potential impact of all risks related to structure and other factors on any trading market for, or trading value of, the Notes.

Accordingly, you should consult your own financial and legal advisors as to the risks entailed by an investment in the Notes and the suitability of investing in the Notes in light of your particular circumstances.

A downgrade of our credit ratings or the ratings of our subsidiaries or other financial institutions could have a material adverse impact on us and the value of and market for the Notes.

Rating agencies continuously evaluate us and our subsidiaries, and their ratings of our long-term and short-term debt are based on a number of factors, including financial strength, as well as factors not entirely within our control, such as conditions affecting the financial services industry generally. In light of these reviews and the continued focus on the financial services industry generally, we and our subsidiaries may not be able to maintain our current credit ratings. Ratings downgrades by a rating agency could have a significant and immediate impact on our funding and liquidity through cash obligations, reduced funding capacity and collateral triggers. A reduction in our or our subsidiaries' credit ratings could also increase our borrowing costs and limit access to the capital markets. These changes could have a material adverse impact on the value of and market for the Notes.

Downgrades in the credit or financial strength ratings assigned to the counterparties with whom we transact could create the perception that our financial condition will be adversely impacted as a result of potential future defaults by such counterparties. Additionally, we could be adversely affected by a general, negative perception of financial institutions caused by the downgrade of other financial institutions. Accordingly, ratings downgrades for other financial institutions could affect the market price of our stock and could limit our access to or increase our cost of capital. These changes could have a material adverse impact on the value of and market for the Notes.

Investors should not rely on indicative or historical data concerning SOFR or Three-Month Term SOFR.

The interest rate during the floating rate period will be determined using Three-Month Term SOFR (unless a Benchmark Transition Event and its related Benchmark Replacement Date occur with respect to Three-Month Term SOFR, in which case the rate of interest will be based on the next-available Benchmark Replacement, which is Compounded SOFR (as described under "Description of Notes"). In the following discussion of SOFR, when we refer to the Notes, we mean the Notes at any time during the floating rate period when the interest rate on the Notes is or will be determined based on SOFR, including Three-Month Term SOFR.

SOFR is published by the Federal Reserve Bank of New York ("FRBNY") and is intended to be a broad measure of the cost of borrowing cash overnight collateralized by U.S. Treasury securities. FRBNY reports that SOFR includes all trades in the Broad General Collateral Rate, plus bilateral U.S. Treasury repurchase agreement ("repo") transactions cleared through the delivery-versus-payment service offered by the Fixed Income Clearing Corporation (the "FICC"), a subsidiary of DTC. SOFR is filtered by FRBNY to remove a portion of the foregoing transactions considered to be "specials." According to FRBNY, "specials" are repos for specific-issue collateral that take place at cash-lending rates below those for general collateral repos because cash providers are willing to accept a lesser return on their cash to obtain a particular security.

FRBNY reports that SOFR is calculated as a volume-weighted median of transaction-level tri-party repo data collected from The Bank of New York Mellon, which currently acts as the clearing bank for the tri-party repo market, as well as General Collateral Finance Repo transaction data and data on bilateral U.S. Treasury repo transactions cleared through the FICC's delivery-versus-payment service. FRBNY states that it obtains information from DTCC Solutions LLC, an affiliate of DTC.

FRBNY currently publishes SOFR daily on its website at

https://www.newyorkfed.org/markets/reference-rates/sofr. FRBNY states on its publication page for SOFR that use of SOFR is subject to important disclaimers,

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limitations and indemnification obligations, including that FRBNY may alter the methods of calculation, publication schedule, rate revision practices or availability of SOFR at any time without notice. The foregoing Internet website is an inactive textual reference only, meaning that the information contained on the website is not part of this prospectus supplement or the accompanying prospectus or incorporated by reference herein or therein.

In 2021, the Alternative Reference Rates Committee (the "ARRC") convened by the Federal Reserve and FRBNY formally recommended the use of the CME Group's computation of forward-looking SOFR term rates, which are calculated by the CME Group based on SOFR futures. It is currently anticipated that Three-Month Term SOFR, for purposes of the Notes, will be based on the CME Group's forward-looking SOFR term rates with a tenor of three months.

FRBNY started publishing SOFR in 2018. FRBNY has also started publishing historical indicative SOFRs dating back to 2014, although such historical indicative data inherently involves assumptions, estimates and approximations. Similarly, certain historical Three-Month Term SOFR data is available from CME Group. Investors should not rely on any such historical data, indicative or otherwise, or on any historical changes or trends in SOFR Three-Month Term SOFR as an indicator of the future performance of SOFR or Three-Month Term SOFR.

Term SOFR and SOFR may be more volatile than other benchmark or market rates.

Since the initial publication of SOFR, daily changes in the rate have, on occasion, been more volatile than daily changes in comparable benchmark or market rates, and Term SOFR and SOFR over time may bear little or no relation to the historical actual or historical indicative data. In addition, the return on and value of the Notes may fluctuate more than floating rate securities that are linked to less volatile rates.

Changes in Term SOFR and SOFR could adversely affect holders of the Notes and the trading prices for the Notes.

Because Term SOFR and SOFR are based on data received from other sources, we have no control over its determination, calculation or publication. There is no assurance that either SOFR or Term SOFR will not be discontinued or fundamentally altered in a manner that is materially adverse to the interests of investors in the Notes. If the manner in which Term SOFR or SOFR are calculated is changed, that change may result in a reduction in the amount of interest that accrues on the Notes during the floating rate period, which may adversely affect the trading prices of the Notes. Further, if the Benchmark rate on the Notes during the floating rate period on any determination date declines to zero or becomes negative, the Benchmark will be deemed to equal zero. In addition, once the Benchmark rate for the Notes for each interest period during the floating rate period is determined by the calculation agent on the determination date, interest on the Notes will accrue based on such Benchmark rate for the applicable interest period and will not be subject to change during such interest period. There is no assurance that changes in Term SOFR or SOFR could not have a material adverse effect on the yield on, value of and market for the Notes.

SOFR and Term SOFR differ fundamentally from, and may not be a comparable substitute for, U.S. dollar LIBOR.

In 2017, the ARRC announced SOFR as its recommended alternative to the London interbank offered rate ("LIBOR") for U.S. dollar obligations. However, because SOFR is a broad U.S. Treasury repo financing rate that represents overnight secured funding transactions, it differs fundamentally from LIBOR. For example, SOFR is a secured overnight rate, while LIBOR is an unsecured rate that represents interbank funding over different maturities. In addition, because SOFR is a transaction-based rate, it is backward-looking, whereas LIBOR is forward-looking. Because of these and other differences, there is no assurance that SOFR will perform in the same way as LIBOR would have performed at any time, and there is no guarantee that it is a comparable

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substitute for LIBOR. While Term SOFR operates more similarly to LIBOR in that it is forward looking, the market data that underlies the determination of Term SOFR is based on SOFR which, as noted above, is fundamentally different from the market data that was used to determine LIBOR. As a result, there is no assurance that Term SOFR will perform in the same way as LIBOR would have performed at any time, and there is no guarantee that it is a comparable substitute for LIBOR.

The interest rate for the Notes during the applicable floating rate period may be determined based on a rate other than Three-Month Term SOFR.

Under the terms of the Notes, the interest rate on the Notes for each interest period during the applicable floating rate period will be based on Three-Month Term SOFR, a forward-looking term rate for a tenor of three months that will be based on SOFR. Uncertainty surrounding the adoption and use of forward-looking term rates based on SOFR could have a material adverse effect on the return on, value of, and market for the Notes. Use and adoption of Three-Month SOFR or forward-looking term rates based on SOFR may require updates to systems and operational processes to facilitate the calculation and determination thereof. If, at the commencement of the floating rate period for the Notes, we determine that the use of a forward-looking rate for a tenor of three months based on SOFR is not administratively feasible, then the next-available Benchmark Replacement under the benchmark transition provisions will be used to determine the interest rate on the Notes during the applicable floating rate period (unless a Benchmark Transition Event and its related Benchmark Replacement Date occur with respect to that next-available Benchmark Replacement).

Under the terms of the Notes, the calculation agent (which may be us) is expressly authorized to make determinations, decisions or elections with respect to technical, administrative or operational matters that it decides are appropriate to reflect the use of Three-Month Term SOFR as the interest rate basis for the Notes, which are defined in the terms of the Notes as "Three-Month Term SOFR Conventions." Such determination and implementation of any Three-Month Term SOFR Conventions could result in adverse consequences to the amount of interest that accrues on the Notes during the applicable floating rate period, which could adversely affect the return on, value of and market for the Notes.

Any Benchmark Replacement may not be the economic equivalent of Three-Month Term SOFR.

Under the benchmark transition provisions of the Notes, if the calculation agent determines that a Benchmark Transition Event and its related Benchmark Replacement Date have occurred with respect to Three-Month Term SOFR, then the floating interest rate on the Notes for each interest period during the floating rate period will be determined using the next-available Benchmark Replacement (which may include a related Benchmark Replacement Adjustment). However, the Benchmark Replacement may not be the economic equivalent of Three-Month Term SOFR. For example, Compounded SOFR, the first-available Benchmark Replacement, is the compounded average of the daily SOFR calculated in arrears, while Three-Month Term SOFR is intended to be a forward-looking rate with a tenor of three months. In addition, very limited market precedent exists for securities that use Compounded SOFR as the rate basis, and the method for calculating Compounded SOFR in those precedents varies. Further, the ISDA Fallback Rate (as defined under "Description of the Notes"), which is another Benchmark Replacement, has not yet been established and may change over time.

The implementation of Benchmark Replacement Conforming Changes could adversely affect holders of the Notes.

Under the benchmark transition provisions of the Notes, if Three-Month Term SOFR has been discontinued or if a particular Benchmark Replacement or Benchmark Replacement Adjustment cannot be determined, then the next-available Benchmark Replacement or Benchmark Replacement Adjustment will apply. These replacement rates and adjustments may be selected or formulated by: (1) the Relevant Governmental Body (such as the ARRC or FRBNY); (2) the International Swaps and Derivatives Association, Inc. ("ISDA"); or (3) in

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certain circumstances, the calculation agent, which may be us. In addition, the benchmark transition provisions expressly authorize the calculation agent (which may be us) to make certain changes, which are defined in the terms of the Notes as "Benchmark Replacement Conforming Changes," with respect to, among other things, the determination of interest periods, and the timing and frequency of determining rates and making payments of interest. The application of a Benchmark Replacement and Benchmark Replacement Adjustment, and any implementation of Benchmark Replacement Conforming Changes, could result in adverse consequences to the amount of interest that accrues on the Notes during any interest period during the floating rate period, which could adversely affect the yield on, value of and market for the Notes. Further, there is no assurance that the characteristics of any Benchmark Replacement will be similar to the then-current Benchmark rate that it is replacing, or that any Benchmark Replacement will produce the economic equivalent of the then-current Benchmark rate that it is replacing.

Also, since SOFR and Term SOFR are a relatively new market indices, SOFR-linked debt securities may not have an established trading market when issued, and an established trading market may never develop or may not be very liquid. Market terms for debt securities indexed to SOFR or Term SOFR, such as the spread over the index reflected in interest rate provisions, may evolve over time, and trading prices of the Notes may be lower than those of later-issued SOFR-linked debt securities as a result. Similarly, if Term SOFR or SOFR does not prove to be widely used in securities similar to the Notes, the trading price of the Notes may be lower than those of debt securities linked to such rates that are more widely used. Debt securities indexed to Term SOFR (as the Notes will be) may not be able to be sold at all or may not be able to be sold at prices that will provide a yield comparable to similar investments that have a developed secondary market, and may consequently suffer from increased pricing volatility and market risk.

A change in the Benchmark interest rate may be treated as a significant modification of the Notes for tax purposes, which could result in taxable gain or loss to holders.

If a term of the Notes, such as the interest rate, is altered such that the Notes are impacted to a degree that is economically significant, the Notes will be treated as exchanged for the modified notes for federal tax purposes. A deemed exchange of the Notes could result in gain or loss to the holders. Thus, if the Benchmark interest rate is replaced with a rate other than the Three-Month Term SOFR, such replacement could adversely affect the holders of the Notes.

We or an affiliate of ours will or could have authority to make determinations and elections that could affect the return on, value of and market for the Notes.

Under the terms of the Notes, we may make certain determinations, decisions and elections with respect to the Benchmark rate on the Notes during the floating rate period, including, without limitation, any determination, decision or election required to be made by the calculation agent that the calculation agent fails to make. We will make any such determination, decision or election in our sole discretion, and any such determination, decision or election that we make could affect the amount of interest that accrues on the Notes during any interest period in the floating rate period. If the calculation agent fails, when required, to make a determination that a Benchmark Transition Event and its related Benchmark Replacement Date have occurred, or fails, when required, to determine the Benchmark Replacement and Benchmark Replacement Adjustment, then we will make those determinations in our sole discretion. Furthermore, we or an affiliate of ours may serve as calculation agent. We expect to act as the initial calculation agent and, though we will appoint a calculation agent prior to the commencement of the floating rate period, we may appoint ourselves or an affiliate and we cannot assure you that we will appoint an independent third-party calculation agent at any time. Any exercise of discretion by us under the terms of the Notes, including, without limitation, any discretion exercised by us or by an affiliate acting as calculation agent, could present a conflict of interest. In making the required determinations, decisions and elections, we or an affiliate of ours acting as calculation agent may have economic interests that are adverse to the interest of the holders of the Notes, and those determinations, decisions or elections could have a material adverse effect on the yield on, value of and market for the Notes. All determinations, decisions or elections by us, or by us or an affiliate acting as calculation agent, under the terms of the Notes will be conclusive and binding absent manifest error.

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The Notes may be issued with original issue discount for U.S. federal income tax purposes.

The Notes may be issued with original issue discount for U.S. federal income tax purposes. In such case, holders subject to U.S. federal income taxation, whether on the cash or accrual method of tax accounting, generally would be required to include any amounts representing original issue discount in gross income (as ordinary income) as the original issue discount accrues on a constant yield to maturity basis, in advance of the receipt of cash payments to which such income is attributable. See "Material U.S. Federal Income Tax Considerations."

The use of the net proceeds from the sale of the Notes will be at the discretion of our management and could change depending on unforeseen events or changes in current business conditions or our circumstances.

While our current intention is to use the net proceeds from this offering to repay existing indebtedness, including the redemption in full of our 2030 Notes, of which $125.0 million in principal amount is currently outstanding, and to support growth initiatives at the Company's subsidiaries and for general corporate purposes, as discussed further under "Use of Proceeds" below, our management will have broad discretion in the use of the net proceeds from the sale of the Notes. The descriptions in this prospectus supplement of our use of the proceeds from the sale of the Notes represent our current intentions based upon our present plans and business conditions. The occurrence of any unforeseen events or change in business conditions, however, could result in the application of the net proceeds of the offering in a manner other than as described in this prospectus supplement.

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USE OF PROCEEDS

We estimate that the net proceeds from this offering will be approximately $181.9 million, after deducting the underwriting discount and our estimated offering expenses. We intend to use the net proceeds from this offering to repay existing indebtedness, including the redemption in full of the 2030 Notes, of which $125.0 million in principal amount is currently outstanding, to support growth initiatives at the Company's subsidiaries and for general corporate purposes, which may include providing capital to support our organic growth or growth through strategic acquisitions, financing investments, capital expenditures, repurchasing shares of our common stock and for investments in the Bank as regulatory capital.

The 2030 Notes currently bear interest at a floating rate of Three-Month Term SOFR, plus a spread of 509.5 basis points, payable quarterly in arrears on February 15, May 15, August 15 and November 15 of each year. The 2030 Notes are scheduled to mature on May 15, 2030. Prior to May 15, 2030, (i) we may redeem the 2030 Notes, in whole but not in part, only under certain limited circumstances set forth in the indenture governing the 2030 Notes and (ii) we may elect to early redeem the 2030 Notes, in whole or in part, on any future interest payment date, at a redemption price equal to 100% of the principal amount plus accrued and unpaid interest, if any, to, but excluding, the redemption date, subject in each case to regulatory approval to the extent such regulatory approval is then required.

The foregoing represents our intentions based upon our present plans and other business conditions. The occurrence of unforeseen events or changed business conditions, however, could result in the application of the net proceeds of the offering in a manner other than as described in this prospectus supplement.

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CAPITALIZATION

The following table shows our capitalization as of June 30, 2025:

You should read this table in conjunction with our consolidated financial statements, the related notes and other financial information contained in our Annual Report on Form 10-K for our fiscal year ended December 31, 2024 and our Quarterly Report on Form 10-Q for our fiscal quarter ended June 30, 2025, which are incorporated by reference in this prospectus supplement and the accompanying prospectus. See "Where You Can Find More Information."

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DESCRIPTION OF THE NOTES

We will issue the Notes under the Base Indenture, as supplemented by the First Supplemental Indenture. You may request a copy of the Indenture from us as described under "Incorporation of Certain Documents by Reference." We have summarized the material terms of the Indenture and the Notes below, but the summary does not purport to be complete and is subject to and qualified in its entirety by reference to the Indenture and the Notes. The following description of the terms of the Indenture and the Notes supplements and, to the extent inconsistent therewith, replaces and supersedes the description of the general terms and provisions of the subordinated debt securities in the accompanying prospectus.

You should read the Indenture and the Notes because they, and not this description, define your rights as holders of the Notes. For purposes of this section, references to "OceanFirst," the "Company," "we," "us" and "our" include only OceanFirst and not any of its subsidiaries.

General

The Notes offered hereby will be issued under a subordinated debt indenture, dated as of October 29, 2025, as amended and supplemented by a first supplemental indenture, dated as of October 29, 2025, between the Company and Wilmington Trust, National Association, as trustee.

The Notes will be our general unsecured, subordinated obligations and will rank senior to our existing fixed/floating rate junior subordinated deferrable interest debentures, and equally with all of our other unsecured, subordinated obligations from time to time outstanding, including the 2030 Notes. The Notes will rank junior to all of our existing and future Senior Indebtedness (as defined below) to the extent and in the manner set forth in the Indenture. In addition, the Notes will be effectively subordinated to all of our secured indebtedness to the extent of the value of the collateral securing such indebtedness. The Notes will be structurally subordinated to all of the existing and future liabilities and obligations of our subsidiaries, including the deposit liabilities and claims of other creditors of our subsidiary bank, OceanFirst Bank N.A. See "-Subordination." The Notes will be obligations of OceanFirst only and will not be obligations of, and will not be guaranteed by, any of our subsidiaries.

The Notes will mature on November 15, 2035 (the "Maturity Date"), unless previously redeemed or otherwise accelerated. The Notes are not convertible into, or exchangeable for, equity securities, other securities, or assets or property of the Company or its subsidiaries. There is no sinking fund for the Notes. We intend for the Notes to qualify (subject to applicable limitations) as Tier 2 capital under applicable capital regulations, guidance, and interpretations of the Federal Reserve. We do not intend to apply for the listing of the Notes on any securities exchange or the quotation of the Notes on any quotation system. The Notes will be issued in minimum denominations of $1,000 and integral multiples of $1,000 in excess thereof.

Beginning with the interest payment date of November 15, 2030, and on any interest payment date thereafter, we may, at our option, subject to obtaining the prior approval of the Federal Reserve to the extent such approval is then required under the rules of the Federal Reserve ("Federal Reserve Approval"), redeem the Notes, in whole or in part, at a price equal to 100% of the principal amount of the Notes to be redeemed plus any accrued and unpaid interest to, but excluding, the redemption date. The Notes may not be redeemed by us prior to November 15, 2030, except that we may, at our option, subject to Federal Reserve Approval, redeem the Notes in whole, but not in part, prior to maturity, including prior to November 15, 2030, upon the occurrence of a "Tax Event" or a "Tier 2 Capital Event" (as such terms are defined in the Indenture) or if we are required to register as an investment company pursuant to the 1940 Act, in each case, at a price equal to 100% of the principal amount of the Notes to be redeemed plus any accrued and unpaid interest to, but excluding, the redemption date. Any partial redemption will be made in accordance with the applicable procedures of The Depository Trust Company (with its successors, "DTC"). See "- Redemption."

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Further Issues

The Indenture does not limit the amount of Notes that we may issue from time to time in one or more series. The Indenture permits us to increase the principal amount of the Notes by issuing additional Notes on the same terms and conditions as the Notes (except for any differences in the issue price and interest accrued prior to the date of issuance of the additional Notes), and with the same CUSIP number as the Notes, provided that the additional Notes are fungible with the Notes for United States federal income tax purposes. The Notes and any additional Notes issued by the Company will rank equally and ratably and shall be treated as a single series of securities for all purposes under the First Supplemental Indenture.

Interest

From and including the date of original issuance to, but excluding, November 15, 2030 or the date of earlier redemption (the "fixed rate period"), the Notes will bear interest at a rate of 6.375% per annum, payable semi-annually in arrears on May 15 and November 15 of each year (each, a "fixed rate interest payment date"), commencing on May 15, 2026. The last fixed rate interest payment date for the fixed rate period will be May 15, 2030.

From and including November 15, 2030 to, but excluding, the Maturity Date or the date of earlier redemption (the "floating rate period"), the Notes will bear interest at a floating rate per annum equal to the Benchmark rate (which is expected to be Three-Month Term SOFR) plus a spread of 307.5 basis points. For each quarterly interest period during the floating rate period, interest will be payable quarterly in arrears on February 15, May 15, August 15 and November 15 of each year (each, a "floating rate interest payment date" and, together with the fixed rate interest payment dates, the "interest payment dates"), commencing on February 15, 2031. Notwithstanding the foregoing, if the Benchmark rate is less than zero, the Benchmark rate shall be deemed to be zero.

For the purpose of calculating the interest on the Notes for each interest period during the floating rate period when the Benchmark is Three-Month Term SOFR, "Three-Month Term SOFR" means the rate for Term SOFR for a tenor of three months that is published by the Term SOFR Administrator at the Reference Time for any interest period, as determined by the calculation agent after giving effect to the Three-Month Term SOFR Conventions. We will act as the initial calculation agent. All percentages used in or resulting from any calculation of Three-Month Term SOFR will be rounded, if necessary, to the nearest one-hundred-thousandth of a percentage point, with 0.000005% rounded up to 0.00001%.

The following definitions apply to the foregoing definition of Three-Month Term SOFR:

"Benchmark" means, initially, Three-Month Term SOFR; provided that if the calculation agent determines on or prior to the Reference Time that a Benchmark Transition Event and its related Benchmark Replacement Date have occurred with respect to Three-Month Term SOFR or the then-current Benchmark, then "Benchmark" means the applicable Benchmark Replacement.

"FRBNY's Website" means the website of the FRBNY at http://www.newyorkfed.org, or any successor source. The foregoing Internet website is an inactive textual reference only, meaning that the information contained on the website is not part of this prospectus supplement or the accompanying prospectus or incorporated by reference herein or therein.

"Reference Time" with respect to any determination of the Benchmark means (1) if the Benchmark is Three-Month Term SOFR, the date that is two U.S. Government Securities Business Days prior to the start of the relevant floating rate interest period, or such other time determined by the calculation agent after giving effect to the Three-Month Term SOFR Conventions, and (2) if the Benchmark is not Three-Month Term SOFR, the time determined by the calculation agent after giving effect to the Benchmark Replacement Conforming Changes.

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"Relevant Governmental Body" means the Federal Reserve and/or the FRBNY, or a committee officially endorsed or convened by the Federal Reserve and/or the FRBNY or any successor thereto.

"SOFR" means the secured overnight financing rate published by the FRBNY, as the administrator of the Benchmark (or a successor administrator), on the FRBNY's Website.

"Term SOFR" means the forward-looking term rate based on SOFR that has been selected or recommended by the Relevant Government Body.

"Term SOFR Administrator" means CME Group Benchmark Administration Limited (CBA) (or a successor administrator of Three-Month Term SOFR selected by the calculation agent in its reasonable discretion).

"Three-Month Term SOFR Conventions" means any determination, decision or election with respect to any technical, administrative or operational matter (including with respect to the manner and timing of the publication of Three-Month Term SOFR, or changes to the definition of "interest period," timing and frequency of determining Three-Month Term SOFR with respect to each interest period and making payments of interest, rounding of amounts or tenors, and other administrative matters) that the calculation agent decides may be appropriate to reflect the use of Three-Month Term SOFR as the Benchmark in a manner substantially consistent with market practice (or, if the calculation agent decides that adoption of any portion of such market practice is not administratively feasible or if the calculation agent determines that no market practice for the use of Three-Month Term SOFR exists, in such other manner as the calculation agent determines is reasonably necessary).

"U.S. Government Securities Business Day" means any day except for a Saturday, Sunday or a day on which the Securities Industry and Financial Markets Association recommends that the fixed income departments of its members be closed for the entire day for purposes of trading in U.S. government securities.

The terms "Benchmark Replacement," "Benchmark Replacement Conforming Changes," "Benchmark Replacement Date," "Benchmark Transition Event" and "Corresponding Tenor" have the meanings set forth below under the heading "-Effect of Benchmark Transition Event."

Notwithstanding the foregoing paragraphs related to the determination of interest, if the calculation agent determines on or prior to the relevant Reference Time that a Benchmark Transition Event and its related Benchmark Replacement Date (each as defined below) have occurred with respect to Three-Month Term SOFR, then the provisions set forth below under the heading "-Effect of Benchmark Transition Event," which we refer to as the "benchmark transition provisions," will thereafter apply to all determinations of the interest rate on the Notes for each interest period during the floating rate period. In accordance with the benchmark transition provisions, after a Benchmark Transition Event and its related Benchmark Replacement Date have occurred, the interest rate on the Notes for each interest period during the floating rate period will be an annual rate equal to the Benchmark Replacement plus 307.5 basis points.

Absent manifest error, the calculation agent's determination of the interest rate for an interest period for the Notes will be binding and conclusive on you, the trustee and us. The calculation agent's determination of any interest rate, and its calculation of interest payments for any period, will be maintained on file at the calculation agent's principal offices, will be made available to any holder of the Notes upon request and will be provided to the trustee.

Interest shall be calculated on the basis of a 360-day year consisting of twelve 30-day months during the fixed rate period and on the basis of a 360-day year and the actual number of days elapsed during the floating rate period. Dollar amounts resulting from that calculation will be rounded to the nearest cent, with one-half cent being rounded upward.

Interest on the Notes, subject to certain exceptions, will accrue during the applicable interest period. When we use the term "interest period," we mean the period from and including the immediately preceding interest

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payment date in respect of which interest has been paid or duly provided for or, if no interest has been paid or duly provided for, from and including the date of issuance of the Notes to, but excluding, the applicable interest payment date or the Maturity Date or date of earlier redemption, if applicable. If a fixed rate interest payment date or the Maturity Date falls on a day that is not a business day, then the interest payment or the payment of principal and interest at maturity will be paid on the next succeeding business day, but the payments made on such dates will be treated as being made on the date that the payment was first due and the holders of the Notes will not be entitled to any further interest or other payments. If a floating rate interest payment date falls on a day that is not a business day, then such floating rate interest payment date will be postponed to the next succeeding business day unless such day falls in the next succeeding calendar month, in which case such floating rate interest payment date will be accelerated to the immediately preceding business day, and, in each such case, the amounts payable on such business day will include interest accrued to, but excluding, such business day.

Interest on each Note will be payable to the person in whose name such Note is registered on the fifteenth day immediately preceding the applicable interest payment date, whether or not such day is a business day. Any interest which is payable, but is not punctually paid or duly provided for, on any interest payment date shall cease to be payable to the holder on the relevant record date by virtue of having been a holder on such date, and such defaulted interest may be paid by us to the person in whose name the Notes are registered at the close of business on a special record date for the payment of defaulted interest, or in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Notes may be listed. However, interest that is paid on the Maturity Date will be paid to the person to whom the principal will be payable. Interest will be payable by wire transfer in immediately available funds in U.S. dollars at the office of the principal paying agent or, at our option in the event the Notes are not represented by global notes, by check mailed to the address of the person specified for payment in the preceding sentences.

If the then-current Benchmark is Three-Month Term SOFR, the calculation agent will have the right to establish the Three-Month Term SOFR Conventions, and if any of the foregoing provisions concerning the calculation of the interest rate and interest payments during the floating rate period are inconsistent with any of the Three-Month Term SOFR Conventions determined by the calculation agent, then the relevant Three-Month Term SOFR Conventions will apply. Furthermore, if the calculation agent determines that a Benchmark Transition Event and its related Benchmark Replacement Date have occurred with respect to Three-Month Term SOFR at any time when any of the Notes are outstanding, then the foregoing provisions concerning the calculation of the interest rate and interest payments during the floating rate period will be modified in accordance with the benchmark transition provisions.

"Business day" means (i) each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in New York are authorized or obligated by law or executive order to close or (ii) a day on which the corporate trust office of the trustee is not closed for business; provided, that, when used in connection with an amount that bears interest at a rate based on SOFR or Term SOFR or any direct or indirect calculation or determination of SOFR or Term SOFR, the term "business day" means any such day that is also a U.S. Government Securities Business Day.

Ranking

The Notes are our general unsecured, subordinated obligations and are:

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Subordination

The Notes are junior in right of payment to the prior payment in full of all our Senior Indebtedness. This means that, under certain circumstances where we may not be making payments on all of our debt obligations as they become due, the holders of all of our Senior Indebtedness will be entitled to receive payment in full of all amounts that are due or will become due on their debt securities before the holders of the Notes will be entitled to receive any amounts under the Notes. These circumstances include when we make a payment or distribute assets to creditors upon our liquidation, dissolution, winding up or reorganization.

These subordination provisions mean that if we are insolvent, a direct holder of a specific amount of our Senior Indebtedness may ultimately receive more of our assets than a direct holder of the same amount of Notes, and our creditor that is owed a specific amount may ultimately receive more of our assets than a direct holder of the same amount of Notes. The Indenture does not limit our ability to incur Senior Indebtedness or general obligations, including indebtedness ranking equally with the Notes or secured debt.

Holders of the Notes may not accelerate the maturity of the Notes, except upon an event of default. See "-Events of Default" below.

The Indenture provides that, unless all principal of and any premium or interest on Senior Indebtedness has been paid in full, no payment or other distribution may be made in respect of any Notes under the following circumstances:

If the trustee or any holders of Notes receive any payment or distribution that is prohibited under the subordination provisions, and if this fact is made known to the trustee or holders at or prior to the time of such payment or distribution, then the trustee or the holders will have to pay over that money to us.

Further, in the event of any insolvency or bankruptcy case or proceedings, or any receivership, liquidation, reorganization, assignment for the benefit of creditors or other similar proceedings or events involving us or our assets, any creditors in respect of general obligations will be entitled to receive payment in full of all amounts due or to become due on or in respect of such general obligations, before any amount is made available for payment or distribution to the holders of the Notes.

Even if the subordination provisions prevent us from making any payment when due on the Notes, we will be in default on our obligations under the Notes if we do not make the payment when due. This means that the trustee and the holders of Notes can take action against us, but they will not receive any money until the claims of the holders of Senior Indebtedness have been fully satisfied.

The Indenture allows the holders of Senior Indebtedness to obtain a court order requiring us and any holder of Notes to comply with the subordination provisions.

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The Indenture defines "Senior Indebtedness" as:

However, Senior Indebtedness does not include:

As of June 30, 2025, the Company had no Senior Indebtedness outstanding on a consolidated basis. The Notes and the Indenture do not contain any limitation on the amount of Senior Indebtedness that we may hereafter incur.

We are a financial holding company and substantially all of our assets are held by our direct and indirect subsidiaries. We rely on dividends and other payments or distributions from our subsidiaries to pay the interest on our debt obligations (such as the Notes offered hereby), which interest expense was $4.2 million for the six months ended June 30, 2025 and $7.2 million and $7.1 million for the years ended December 31, 2024 and 2023, respectively (holding company only). Federal and state bank regulations impose certain restrictions on the ability of our bank subsidiaries to pay dividends directly or indirectly to us, to make any extensions of credit to us or certain of our affiliates and to invest in our stock or securities. These regulations also prevent us from borrowing from our bank subsidiaries unless the loans are secured by collateral. Accordingly, we may not have access to sufficient cash to make payments on the Notes. See "Risk Factors" in this prospectus supplement and the accompanying prospectus and Item "1A. Risk Factors" in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024.

Because we are a holding company, our right and the rights of our creditors, including holders of the Notes, to participate in any distribution of assets of any of our subsidiaries upon their liquidation, reorganization,

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dissolution, winding up or otherwise would be subject to the prior claims of creditors of that subsidiary (except to the extent that we are a creditor with a recognized claim). In the event of any such distribution of assets of our bank subsidiaries due in part to their status as insured depository institutions, the claims of depositors and other general or subordinated creditors of such bank subsidiaries would be entitled to priority over claims of shareholders of such bank subsidiary, including us as its parent holding company and any creditor of ours, such as holders of the Notes. As of June 30, 2025, the Bank had $10.4 billion of deposits, $938.7 million of FHLB advances, including advances with an original maturity term of less than one year, $61.5 million of customer repurchase agreements and $52.5 million of other borrowings, to which the Notes will be structurally subordinated.

No Additional Amounts

In the event that any payment on the Notes is subject to withholding of any U.S. federal income tax or other tax or assessment (as a result of a change in law or otherwise), we will not pay additional amounts with respect to such tax or assessment. For a discussion relating to certain U.S. federal income tax consequences of the ownership and disposition of the Notes, see "U.S. Federal Income Tax Considerations."

Redemption

We may, at our option, beginning with the interest payment date of November 15, 2030, but not prior thereto (except upon the occurrence of certain events specified below), and on any interest payment date thereafter, redeem the Notes, in whole or in part, from time to time, subject to obtaining the Federal Reserve Approval, at a price equal to 100% of the principal amount of the Notes being redeemed plus accrued and unpaid interest to, but excluding, the date of redemption.

The Notes may not otherwise be redeemed prior to the Maturity Date, except that we may also, at our option, redeem the Notes, in whole, but not in part, subject to obtaining the Federal Reserve Approval, at a redemption price equal to 100% of the principal amount of the Notes being redeemed plus accrued and unpaid interest to, but excluding, the date of redemption, at any time, including before November 15, 2030, upon the occurrence of:

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In the event of any redemption of the Notes, we will deliver or cause to be delivered a notice of redemption (which notice may be conditional in our discretion on one or more conditions precedent, and the redemption date may be delayed until such time as any or all of such conditions have been satisfied or revoked by us if we determine that such conditions will not be satisfied) to each holder of Notes (with a copy to the trustee) not less than 15 nor more than 60 days prior to the redemption date.

Any partial redemption will be made in accordance with DTC's applicable procedures among all of the holders of the Notes. If any Note is to be redeemed in part only, the notice of redemption relating to such Note shall state that it is a partial redemption and the portion of the principal amount thereof to be redeemed. A replacement Note in principal amount equal to the unredeemed portion thereof will be issued in the name of the holder thereof upon cancellation of the original note. The Notes are not subject to redemption or prepayment at the option of the holders.

Events of Default

The only "events of default" with respect to the Notes under the Indenture are certain events related to our bankruptcy or insolvency, whether voluntary or involuntary, or certain events related to the insolvency of the Bank, which represents 50% or more of our consolidated assets or any subsidiary of ours in the future which represents 50% or more of our consolidated assets. If an event of default with respect to the Notes occurs and is continuing, the principal amount of all of the Notes shall become and be immediately due and payable without any declaration or other action on the part of the trustee or any holder of the Notes. If an event of default with respect to Notes occurs and is continuing, the trustee may enforce its rights and the rights of the holders of the Notes by any judicial proceedings that the trustee deems to be most effectual to do so.

The maturity of the Notes may only be accelerated upon the occurrence of an event of default described above. There is no right of acceleration of the payment of principal of the Notes upon a "default" in the payment of principal of or interest on the Notes or in the performance of any of our covenants or agreements contained in the Notes, in the Indenture or any of our other obligations or liabilities, including the events described as a "default" below. For purposes of the Notes, "default" means (i) a default in the payment of principal of the Notes when due, whether at maturity, by acceleration of maturity or otherwise, (ii) a default in the payment of interest on the Notes when due, which continues for 30 days, and (iii) our default in the performance, or breach, of any term, covenant or agreement in the Indenture applicable to us and the Notes, and continuance of such default or breach for a period of 90 days after there has been given, by registered or certified mail, to us by the trustee or to us and the trustee by the holders of at least 25% in aggregate principal amount of the outstanding Notes a written notice specifying such default or breach and requiring it to be remedied and stating that such notice is a notice of default under the Indenture. If a default in the payment of principal of or interest on the Notes occurs and is continuing under the Indenture, the trustee and holders of Notes will have a right to institute suit directly against us for the collection of such overdue payment. Other than upon a default in the payment of principal of or interest on the Notes, the holders of the Notes will have limited rights to institute proceedings to enforce the terms of the Indenture.

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Modification

From time to time, we, together with the trustee, may, without the consent of the holders of Notes, amend the Indenture for one or more of the following purposes:

The Indenture permits us and the trustee, with the consent of the holders of a majority in aggregate principal amount of each series of the outstanding Notes affected thereby, to modify the Indenture in a manner affecting the rights of the holders of the Notes of such series; provided that no modification may, without the consent of the holders of each outstanding note affected:

Consolidation, Merger, Sale of Assets and Other Transactions

We will not consolidate with or merge into any other person or convey, transfer or lease all or substantially all of our properties and assets to any person, unless:

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The general provisions of the Indenture do not limit the rights of OceanFirst Financial Corp. to enter into transactions, such as a highly-leveraged transaction, that may adversely affect the holders of the Notes.

Satisfaction and Discharge

The Indenture provides that when, among other things, all Notes not previously delivered to the trustee for cancellation:

and we irrevocably deposit or cause to be deposited with the trustee as trust funds in trust for such purpose money in an amount sufficient to pay and discharge the entire indebtedness on the Notes not previously delivered to the trustee for cancellation, for the principal and any premium and interest to the date of such deposit (in the case of Notes which have become due and payable) or to the Maturity Date or the date of redemption, as the case may be;

then, upon our request, the Indenture will cease to be of further effect, and we will be deemed to have satisfied and discharged the Indenture with respect to the Notes. However, we will continue to be obligated to pay all other sums due under the Indenture and to provide the officers' certificates and opinions of counsel described in the Indenture.

Defeasance

We may at any time terminate all of our obligations under the Notes, except for certain obligations, including those respecting the defeasance trust. Our obligations will be deemed to have been discharged if the following applicable conditions have been satisfied:

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Any defeasance of the Notes pursuant to the Indenture shall be subject to our obtaining the prior approval of the Federal Reserve and any additional requirements that the Federal Reserve may impose with respect to defeasance of the Notes. Notwithstanding the foregoing, if, due to a change in law, regulation or policy subsequent to the issue date of the Notes the Federal Reserve does not require that defeasance of instruments be subject to Federal Reserve approval in order for the instrument to be accorded Tier 2 capital treatment, then no such approval of the Federal Reserve will be required for such defeasance.

Effect of Benchmark Transition Event

Benchmark Replacement. If the calculation agent determines that a Benchmark Transition Event and its related Benchmark Replacement Date have occurred on or prior to the Reference Time in respect of any determination of the Benchmark on any date, then the Benchmark Replacement will replace the then-current Benchmark for all purposes relating to the Notes during the floating rate period in respect of such determination on such date and all determinations on all subsequent dates.

Benchmark Replacement Conforming Changes. In connection with the implementation of a Benchmark Replacement, the calculation agent will have the right to make Benchmark Replacement Conforming Changes from time to time.

Certain Defined Terms. As used herein:

"Benchmark Replacement" means the Interpolated Benchmark with respect to the then-current Benchmark, plus the Benchmark Replacement Adjustment for such Benchmark; provided that if (a) the calculation agent cannot determine the Interpolated Benchmark as of the Benchmark Replacement Date or (b) the then-current Benchmark is Three-Month Term SOFR and a Benchmark Transition Event and its related Benchmark Replacement Date have occurred with respect to Three-Month Term SOFR (in which event no Interpolated Benchmark with respect to Three-Month Term SOFR shall be determined), then "Benchmark Replacement" means the first alternative set forth in the order below that can be determined by the calculation agent as of the Benchmark Replacement Date:

"Benchmark Replacement Adjustment" means the first alternative set forth in the order below that can be determined by the calculation agent as of the Benchmark Replacement Date:

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"Benchmark Replacement Conforming Changes" means, with respect to any Benchmark Replacement, any technical, administrative or operational changes (including changes to the definition of "interest period," timing and frequency of determining rates with respect to each interest period and making payments of interest, rounding of amounts or tenors, and other administrative matters) that the calculation agent decides may be appropriate to reflect the adoption of such Benchmark Replacement in a manner substantially consistent with market practice (or, if the calculation agent decides that adoption of any portion of such market practice is not administratively feasible or if the calculation agent determines that no market practice for use of the Benchmark Replacement exists, in such other manner as the calculation agent determines is reasonably necessary).

"Benchmark Replacement Date" means the earliest to occur of the following events with respect to the then-current Benchmark:

For the avoidance of doubt, for purposes of the definitions of Benchmark Replacement Date and Benchmark Transition Event, references to the Benchmark also include any reference rate underlying the Benchmark (for example, if the Benchmark becomes Compounded SOFR, references to the Benchmark would include SOFR).

For the avoidance of doubt, if the event giving rise to the Benchmark Replacement Date occurs on the same day as, but earlier than, the Reference Time in respect of any determination, the Benchmark Replacement Date will be deemed to have occurred prior to the Reference Time for such determination.

"Benchmark Transition Event" means the occurrence of one or more of the following events with respect to the then-current Benchmark:

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"Compounded SOFR" means the compounded average of SOFRs for the applicable Corresponding Tenor, with the rate, or methodology for this rate, and conventions for this rate being established by the calculation agent in accordance with:

For the avoidance of doubt, the calculation of Compounded SOFR shall exclude the Benchmark Replacement Adjustment (if applicable) and the spread of 307.5 basis points per annum.

"Corresponding Tenor" with respect to a Benchmark Replacement means a tenor (including overnight) having approximately the same length (disregarding business day adjustment) as the applicable tenor for the then-current Benchmark.

"Interpolated Benchmark" with respect to the Benchmark means the rate determined for the Corresponding Tenor by interpolating on a linear basis between: (1) the Benchmark for the longest period (for which the Benchmark is available) that is shorter than the Corresponding Tenor, and (2) the Benchmark for the shortest period (for which the Benchmark is available) that is longer than the Corresponding Tenor.

"ISDA" means the International Swaps and Derivatives Association, Inc. or any successor.

"ISDA Definitions" means the 2006 ISDA Definitions published by ISDA, as amended or supplemented from time to time, or any successor definitional booklet for interest rate derivatives published from time to time.

"ISDA Fallback Adjustment" means the spread adjustment (which may be a positive or negative value or zero) that would apply for derivatives transactions referencing the ISDA Definitions to be determined upon the occurrence of an index cessation event with respect to the Benchmark for the applicable tenor.

"ISDA Fallback Rate" means the rate that would apply for derivatives transactions referencing the ISDA Definitions to be effective upon the occurrence of an index cessation date with respect to the Benchmark for the applicable tenor excluding the applicable ISDA Fallback Adjustment.

"Unadjusted Benchmark Replacement" means the Benchmark Replacement excluding the Benchmark Replacement Adjustment.

The terms "FRBNY's Website," "Reference Time," "Relevant Governmental Body," "SOFR" and "Term SOFR" have the meanings set forth above under the heading "-Interest."

Determinations and Decisions

The calculation agent is expressly authorized to make certain determinations, decisions and elections under the terms of the Notes, including with respect to the use of Three-Month Term SOFR as the Benchmark for the floating rate period and under the benchmark transition provisions. Any determination, decision or election that may be made by the calculation agent under the terms of the Notes, including any determination with respect to a tenor, rate or adjustment or of the occurrence or non-occurrence of an event, circumstance or date and any decision to take or refrain from taking any action or any selection:

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Form, Denomination, Transfer, Exchange and Book-Entry Procedures

The Notes offered hereby will be issued only in fully registered form, without interest coupons, and in minimal denominations of $1,000 and integral multiples of $1,000 in excess thereof.

The Notes offered hereby will be evidenced by a global note which will be deposited with, or on behalf of, DTC, or any successor thereto, and registered in the name of Cede & Co., or Cede, as nominee of DTC. Except as set forth below, record ownership of the global note may be transferred, in whole or in part, only to another nominee of DTC or to a successor of DTC or its nominee.

The global note will not be registered in the name of any person, or exchanged for Notes that are registered in the name of any person, other than DTC or its nominee, unless one of the following occurs:

In those circumstances, DTC will determine in whose names any securities issued in exchange for the global note will be registered. Any such Notes in certificated form will be issued in minimum denominations of $1,000 and multiples of $1,000 in excess thereof and may be transferred or exchanged only in such minimum denominations.

DTC or its nominee will be considered the sole owner and holder of the global note for all purposes, and as a result:

The laws of some jurisdictions require that certain kinds of purchasers (for example, certain insurance companies) can only own securities in definitive (certificated) form. These laws may limit your ability to transfer your beneficial interests in the global note to these types of purchasers.

Only institutions (such as a securities broker or dealer) that have accounts with the DTC or its nominee (called "participants") and persons that may hold beneficial interests through participants (including through Euroclear Bank SA/NV or Clearstream Banking, société anonyme, as DTC participants) can own a beneficial interest in the global note. The only place where the ownership of beneficial interests in the global note will appear and the only way the transfer of those interests can be made will be on the records kept by DTC (for their participants' interests) and the records kept by those participants (for interests of persons held by participants on their behalf).

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Secondary trading in bonds and notes of corporate issuers is generally settled in clearing-house (that is, next-day) funds. In contrast, beneficial interests in a global note usually trade in DTC's same-day funds settlement system, and settle in immediately available funds. We make no representations as to the effect that settlement in immediately available funds will have on trading activity in those beneficial interests.

We will make cash payments of interest on and principal of the global note to Cede, the nominee for DTC, as the registered owner of the global note. We will make these payments by wire transfer of immediately available funds on each payment date.

You may exchange or transfer the Notes at the corporate trust office of the trustee for the Notes or at any other office or agency maintained by us for those purposes. We will not require payment of a service charge for any transfer or exchange of the Notes, but OceanFirst Financial Corp. may require payment of a sum sufficient to cover any applicable tax or other governmental charge.

We have been informed that, with respect to any cash payment of interest on or principal of the global note, DTC's practice is to credit participants' accounts on the payment date with payments in amounts proportionate to their respective beneficial interests in the Notes represented by the global note as shown on DTC's records, unless DTC has reason to believe that it will not receive payment on that payment date. Payments by participants to owners of beneficial interests in Notes represented by the global note held through participants will be the responsibility of those participants, as is now the case with securities held for the accounts of customers registered in "street name."

We also understand that neither DTC nor Cede will consent or vote with respect to the Notes. We have been advised that under its usual procedures, DTC will mail an "omnibus proxy" to us as soon as possible after the record date. The omnibus proxy assigns Cede's consenting or voting rights to those participants to whose accounts the Notes are credited on the record date identified in a listing attached to the omnibus proxy.

Because DTC can only act on behalf of participants, who in turn act on behalf of indirect participants, the ability of a person having a beneficial interest in the principal amount represented by the global note to pledge the interest to persons or entities that do not participate in the DTC book-entry system, or otherwise take actions in respect of that interest, may be affected by the lack of a physical certificate evidencing its interest.

DTC has advised us that it will take any action permitted to be taken by a holder of notes (including the presentation of notes for exchange) only at the direction of one or more participants to whose account with DTC interests in the global note are credited and only in respect of such portion of the principal amount of the Notes represented by the global note as to which such participant has, or participants have, given such direction.

DTC has also advised us as follows: DTC is a limited purpose trust company organized under the laws of the State of New York, a "banking organization" within the meaning of the New York Banking Law, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the Uniform Commercial Code, as amended, and a "clearing agency" registered pursuant to the provisions of Section 17A of the Exchange Act. DTC was created to hold securities for its participants and facilitate the clearance and settlement of securities transactions between participants through electronic book-entry changes in accounts of its participants. Participants include securities brokers and dealers, banks, trust companies and clearing corporations and may include certain other organizations. Certain of such participants (or their representatives), together with other entities, own DTC. Indirect access to the DTC system is available to other entities such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly. The rules applicable to DTC and its direct and indirect participants are on file with the SEC.

The policies and procedures of DTC, which may change periodically, will apply to payments, transfers, exchanges and other matters relating to beneficial interests in the global note. We and the trustee have no responsibility or liability for any aspect of DTC's or any participants' records relating to beneficial interests in

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the global note, including for payments made on the global note, and we and the trustee are not responsible for maintaining, supervising or reviewing any of those records.

Calculation Agent

We will appoint a calculation agent for the Notes prior to the commencement of the floating rate period and will keep a record of such appointment at our principal offices, which will be available to any holder of the Notes upon request. In addition, we or an affiliate of ours may assume the duties of the calculation agent. We will act as the initial calculation agent.

The Trustee

The trustee for the holders of Notes issued under the Indenture is Wilmington Trust, National Association. If an event of default with respect to the Notes occurs, and is not cured, the trustee will be required to use the degree of care of a prudent person in the conduct of his or her own affairs in the exercise of its powers. The trustee will be under no obligation to exercise any of its rights or powers under the Indenture at the request of any holders of the Notes, unless they have offered to the trustee security or indemnity satisfactory to the trustee.

Wilmington Trust, National Association, in the future, may be the trustee under other indentures pursuant to which we issue debt. Pursuant to the Trust Indenture Act of 1939, if a default occurs with respect to the securities of any series, the trustee will be required to eliminate any conflicting interest as defined in the Trust Indenture Act or resign as trustee with respect to the securities of that series within 90 days of such default, unless such default were cured, duly waived or otherwise eliminated.

From time to time, we, and one or more of our subsidiaries, may maintain deposit accounts and conduct other banking transactions, including lending transactions, with Wilmington Trust, National Association in the ordinary course of business. Additionally, we maintain banking relationships with Wilmington Trust, National Association and its affiliates in the ordinary course of business. These banking relationships include Wilmington Trust, National Association serving as trustee under indentures involving certain of our trust preferred securities and our outstanding subordinated notes.

Payment and Paying Agents

We will pay principal and interest on the Notes at the corporate trust office of the trustee or at the office of any paying agent that we may designate.

We will pay any interest on the Notes to the registered owner of the Notes at the close of business on the record date for the interest, except in the case of defaulted interest. Interest payable at maturity of the Notes will be paid to the registered holder to whom principal is payable. We may at any time designate additional paying agents or rescind the designation of any paying agent.

Any moneys deposited with the trustee or any paying agent, or then held by us in trust, for the payment of the principal of and interest on any Note that remains unclaimed for two years after the principal or interest has become due and payable will, at our request, be repaid to us, or (if then held by us) be discharged from such trust. After repayment to us, you are entitled to seek payment only from us as a unsecured general creditor.

Governing Law

The Indenture and the Notes are governed by and construed in accordance with the laws of the State of New York.

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CERTAIN ERISA CONSIDERATIONS

The following is a summary of certain considerations associated with the purchase and holding of the Notes by (1) employee benefit plans subject to Title I of the U.S. Employee Retirement Income Security Act of 1974, as amended, which we refer to as "ERISA", (2) plans, individual retirement accounts and other arrangements subject to Section 4975 of the Code, (3) plans subject to any federal, state, local, non-U.S. or other laws or regulations that are similar to Title I of ERISA or Section 4975 of the Code, which we collectively refer to as "Similar Laws", and (4) entities whose underlying assets are considered to include "plan assets" of such employee benefit plans, plans or arrangements (each of which we call a "Plan").

Each fiduciary of a Plan should consider the fiduciary standards of ERISA, to the extent applicable, or any applicable Similar Laws in the context of the Plan's particular circumstances before authorizing an investment in the Notes. Accordingly, among other factors, the fiduciary should consider whether the investment would satisfy the prudence and diversification requirements of ERISA, to the extent applicable, or any applicable Similar Laws and would be consistent with the documents and instruments governing the Plan.

In addition, Section 406 of ERISA and Section 4975 of the Code prohibit Plans subject to such provisions, which we call "ERISA Plans", from engaging in certain transactions involving "plan assets" with persons that are "parties in interest" under ERISA or "disqualified persons" under Section 4975 of the Code with respect to the ERISA Plan. A violation of these "prohibited transaction" rules may result in an excise tax for such persons or other liabilities under ERISA and/or Section 4975 of the Code, unless exemptive relief is available under an applicable statutory or administrative exemption. Employee benefit plans that are governmental plans (as defined in Section 3(32) of ERISA), certain church plans (as defined in Section 3(33) of ERISA) and non-U.S. plans (as described in Section 4(b)(4) of ERISA) are not subject to the requirements of ERISA or Section 4975 of the Code, but may be subject to Similar Laws.

As a result of our business, we and certain of our affiliates may be considered parties in interest or disqualified persons with respect to many ERISA Plans. Prohibited transactions within the meaning of Section 406 of ERISA or Section 4975 of the Code could arise if the Notes were acquired by an ERISA Plan with respect to which an underwriter or we or our affiliate is a party in interest or a disqualified person. For example, if any underwriter or we are a party in interest or disqualified person with respect to an investing ERISA Plan (either directly or, in our case, by reason of our ownership of our subsidiaries), the purchase of any Notes by an ERISA Plan could result in a sale or exchange that is prohibited by Section 406(a)(1)(A) of ERISA and Section 4975(c)(1)(A) of the Code or lending of money or other extension of credit that is prohibited by Section 406(a)(1)(B) of ERISA and Section 4975(c)(1)(B) of the Code, unless exemptive relief were available under an applicable exemption (see below).

The U.S. Department of Labor has issued prohibited transaction class exemptions, or PTCEs, that may provide exemptive relief for direct or indirect prohibited transactions resulting from the purchase, holding or disposition of the Notes. Those class exemptions include:

In addition, ERISA Section 408(b)(17) and Section 4975(d)(20) of the Code provides an exemption for transactions between an ERISA Plan and a party in interest or disqualified person, provided that the party in

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interest or disqualified person is not a fiduciary (or an affiliate) who has or exercises any discretionary authority or control with respect to the investment of the ERISA Plan assets involved in the transaction or renders investment advice with respect to those assets, and is a party in interest or disqualified person solely by reason of being a service provider to the ERISA Plan or having a relationship to a service provider to the ERISA Plan and provided, further that the ERISA Plan pays no more, nor receives no less, than adequate consideration in connection with the transaction (the so-called "service provider exemption"). No assurance can be made that any such exemptions will be available, or that all of the conditions of any such exemptions will be satisfied, with respect to transactions involving the Notes.

Because of the possibility that direct or indirect prohibited transactions or violations of Similar Laws could occur as a result of the purchase, holding or disposition of the Notes by a Plan, the Notes may not be purchased by any Plan, or any person investing the assets of any Plan, unless its purchase, holding and disposition of the Notes will not constitute or result in a non-exempt prohibited transaction under ERISA or Section 4975 of the Code or a violation of any Similar Laws. Any purchaser or holder of the Notes or any interest in the Notes will be deemed to have represented by its purchase and holding of the Notes that either:

Due to the complexity of these rules and the penalties imposed upon persons involved in non-exempt prohibited transactions, it is important that any person considering the purchase of the Notes on behalf of or with the assets of any Plan consult with its counsel regarding the consequences under ERISA, the Code and any applicable Similar Laws of the acquisition, ownership and disposition of the Notes, whether any exemption would be applicable, and whether all conditions of such exemption would be satisfied such that the acquisition and holding of the Notes by the Plan would be entitled to full exemptive relief thereunder.

Nothing herein will be construed as, and the sale of the Notes to a Plan is in no respect, a representation or advice by us or the underwriters (or any of our or their affiliates) as to whether any investment in the Notes would meet any or all of the relevant legal requirements with respect to investment by, or is appropriate for, Plans generally or any particular Plan. The foregoing discussion is merely a summary and should not be construed as legal advice or as complete in all relevant respects.

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MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS

This section describes the material U.S. federal income tax considerations of the acquisition, ownership and disposition of the Notes we are offering. It is not a complete analysis of all the potential tax considerations relating to the Notes. This summary is based upon the provisions of the Code, Treasury Regulations promulgated under the Code, and currently effective administrative rulings and judicial decisions. These authorities may be changed, perhaps with retroactive effect, so as to result in U.S. federal income tax consequences different from those set forth below.

This summary is limited to beneficial owners (referred to in this summary as holders) of the Notes that purchase the Notes upon their initial issuance at their "issue price" (i.e., the first price at which a substantial amount of the Notes is sold for cash to investors (excluding sales to bond houses, brokers or similar persons or organizations acting in the capacity as underwriters, placement agents or wholesalers)) and that will hold the Notes as capital assets within the meaning of Section 1221 of the Code for U.S. federal income tax purposes. This summary does not address the tax considerations arising under the laws of any foreign, state or local jurisdiction. In addition, this discussion does not address any alternative minimum tax provisions of the Code or net investment income tax considerations, nor does it address all U.S. federal income tax considerations that may be applicable to holders' particular circumstances or to holders that may be subject to special tax rules, such as, for example:

If an entity or arrangement classified as a partnership for U.S. federal income tax purposes holds the Notes, the tax treatment of a partner in the partnership will generally depend upon the status of the partner and the activities of the partnership. If you are an entity or arrangement classified as a partnership for U.S. federal income tax purposes that will hold Notes or a partner of such a partnership, you are urged to consult your tax advisor regarding the tax consequences of holding the Notes to you.

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This summary of certain U.S. federal income tax considerations is for general information only and is not tax advice. You are urged to consult your tax advisor with respect to the application of U.S. federal income tax laws to your particular situation as well as any tax considerations arising under other U.S. federal tax laws (such as the estate or gift tax laws) or under the laws of any state, local, foreign or other taxing jurisdiction or under any applicable tax treaty.

U.S. Holders

This subsection describes the tax considerations for a "U.S. holder." You are a "U.S. holder" if you are a beneficial owner of a Note and you are:

Payments of interest and original discount on the Notes. The Notes will initially bear interest at a fixed annual rate. Subsequent to the fixed rate period, the Notes will bear interest at the Benchmark Rate, which is expected to be the Three-Month Term SOFR, plus a fixed spread. The Notes should be treated for U.S. federal income tax purposes as variable rate debt instruments that provide for a single fixed rate followed by a single "qualified floating rate." A qualified floating rate is any variable rate where variations in the value of such rate can reasonably be expected to measure contemporaneous variations in the cost of newly borrowed funds in the currency in which the debt instrument is denominated. Under this characterization, payments treated as qualified stated interest on the Notes generally will be taxable to U.S. holders as ordinary interest income at the time such interest payments are accrued or received, depending on the U.S. holder's regular method of accounting for U.S. federal income tax purposes. Qualified stated interest generally means stated interest that is unconditionally payable in cash at least annually at a single fixed rate, but as discussed below, special rules are applicable to a variable rate debt instrument.

For U.S. federal income tax purposes, original issue discount is the excess of the stated redemption price at maturity of a debt instrument over its issue price (as defined above) if such excess equals or exceeds a specified de minimis amount (generally 1/4 of 1% of the debt instrument's stated redemption price at maturity multiplied by the number of complete years to maturity of such debt instrument). The stated redemption price at maturity of a debt instrument is the sum of all payments provided by the debt instrument other than payments of qualified stated interest. A U.S. holder (regardless of its method of tax accounting) will be required to include original issue discount, if any, in ordinary income as it accrues in accordance with a constant yield method based on a compounding of interest. Any amounts included in income as original issue discount with respect to a Note, if any, will increase a U.S. holder's adjusted basis in the Note.

Under applicable Treasury Regulations, to determine the amount of qualified stated interest and original issue discount in respect of variable rate debt instruments such as the Notes, an equivalent fixed rate debt instrument must be constructed. The equivalent fixed rate debt instrument is a hypothetical instrument that has terms that are identical to those of the Notes, except that the equivalent fixed rate debt instrument provides for fixed rate substitutes in lieu of the actual rates on the Notes. The equivalent fixed rate debt instrument for the Notes is constructed in the following fashion: (1) first, the initial fixed rate is replaced with a qualified floating rate such that the fair market value of the Notes as of the Notes' issue date would be approximately the same as the fair market value of an otherwise identical debt instrument that provides for the replacement qualified

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floating rate rather than the fixed rate, and (2) second, each qualified floating rate (including the qualified floating rate determined under (1) above) is converted into a fixed rate substitute (which, in each case, generally will be the value of each qualified floating rate as of the issue date of the Notes).

After the equivalent fixed rate debt instrument has been constructed pursuant to the foregoing rules, the amount of qualified stated interest and original issue discount, if any, are determined for the equivalent fixed rate debt instrument by applying the general original issue discount rules to the equivalent fixed rate debt instrument, and a U.S. holder of the Notes will account for such original issue discount, if any, and qualified stated interest as if the U.S. holder held the equivalent fixed rate debt instrument. For each accrual period, appropriate adjustments will be made to the amount of qualified state interest or original issue discount assumed to have been accrued or paid with respect to the equivalent fixed rate debt instrument in the event that such amounts differ from the actual amount of interest accrued or paid on the Notes during the accrual period.

The Treasury Regulations provide special rules for determining the yield and maturity of a debt instrument, such as the Notes, that provide an issuer with an unconditional option to redeem the instrument at specified times. The Treasury Regulations generally deem an issuer to exercise a redemption option in a manner that minimizes the yield on the debt instrument for purposes of determining whether a debt instrument is issued with original issue discount. If, as of the issue date, the initial fixed rate substitute on the equivalent fixed rate debt instrument (as determined in the manner described above) is equal to or greater than the fixed rate substitute of the floating rate (as determined in the manner described above), the Notes will be presumed not to be redeemed, and the qualified stated interest and original issue discount with respect to the Notes will be calculated as described above. Under such circumstances, the Notes may be issued with original issue discount. If, however, as of the issue date, the initial fixed rate substitute on the equivalent fixed rate debt instrument (as determined in the manner described above) is less than the fixed rate substitute of the floating rate (as determined in the manner described above), the yield on the Notes will be minimized if the Notes are redeemed immediately before the change in the interest rate at the end of the fixed rate period, and, therefore, the Notes will be treated as maturing on such date and issued without original issue discount. This presumption is made solely for purposes of determining whether the Notes are issued with original issue discount for U.S. federal income tax purposes and is not an indication of our intention to redeem or not to redeem the Notes at any time. If, contrary to this presumption, the Notes are not redeemed prior to the change in the interest rate at the end of the fixed rate period, then, solely for original issue discount purposes, the Notes will be deemed to be reissued at their adjusted issue price on the date that they are not redeemed, and therefore as issued without original issue discount. This deemed reissuance should not give rise to taxable gain or loss to U.S. holders.

Sale, exchange, retirement or other taxable disposition. Upon the sale, exchange, retirement or other taxable disposition of a Note, a U.S. holder will recognize taxable gain or loss equal to the difference between the amount realized on such disposition (except to the extent any amount realized is attributable to accrued but unpaid interest, which will be treated as a payment of interest) and the U.S. holder's adjusted tax basis in the Note. U.S. holder's adjusted tax basis in a Note generally will be its cost increased by the amounts of any original issue discount previously included in income by the U.S. holder with respect to the Note and decreased by any payments (other than amounts treated as qualified stated interest received) on the Note. Gain or loss recognized on the disposition of a Note generally will be capital gain or loss, and will be long-term capital gain or loss if, at the time of the disposition, the U.S. holder's holding period for the Note is more than one year. Long-term capital gains of non-corporate taxpayers are generally eligible for preferential rates of taxation. The deductibility of capital losses is subject to certain limitations.

Information reporting and backup withholding. Information returns are required to be filed with the IRS in connection with payments on the Notes and proceeds received from a sale or other disposition of the Notes unless the U.S. holder is an exempt recipient. U.S. holder may also be subject to backup withholding on these payments in respect of the U.S. holder's Notes unless the U.S. holder provides a taxpayer identification number and otherwise complies with applicable requirements of the backup withholding rules or the U.S. holder provides proof of an applicable exemption. Amounts withheld under the backup withholding rules are not additional taxes

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and may be refunded or credited against the U.S. holder's U.S. federal income tax liability, provided the required information is timely furnished to the IRS.

Non-U.S. Holders

This subsection describes the tax considerations for a "non-U.S. holder." You are a "non-U.S. holder" if you are the beneficial owner of a Note that is not an entity or arrangement classified as a partnership for U.S. federal income tax purposes (which, as indicated above, we do not address herein) and is:

Payments of interest. Subject to the discussion under "-Information reporting and backup withholding" and "-FATCA" below, payments of principal and interest on the Notes to a non-U.S. holder generally will be exempt from U.S. federal income or withholding tax if, in the case of the payments of interest:

If a non-U.S. holder cannot satisfy one of the first three requirements described above and interest on the Notes is not exempt from withholding because it is effectively connected with the non-U.S. holder's conduct of a trade or business in the United States (and, if required by an applicable income tax treaty, is attributable to the non-U.S. holder's U.S. permanent establishment or fixed base), as described below, payments of interest on the Notes will be subject to withholding tax at a rate of 30%, or the rate specified by an applicable treaty.

Sale, exchange or other taxable disposition. Subject to the discussions of FATCA and information reporting and backup withholding below, a non-U.S. holder generally will not be subject to U.S. federal income or withholding tax on gain realized on a sale, redemption or other taxable disposition of Notes, unless the gain is effectively connected with the non-U.S. holder's conduct of a trade or business in the United States (and, if required by an applicable income tax treaty, is attributable to the non-U.S. holder's U.S. permanent establishment or fixed base), as described below. However, any proceeds attributable to accrued interest will be treated as described in "-Payments of interest" above.

Income or gain effectively connected with a U.S. trade or business. If interest or gain on the Notes is effectively connected with a non-U.S. holder's conduct of a trade or business in the United States (and, if required by an applicable income tax treaty, is attributable to a U.S. permanent establishment or fixed base maintained by a non-U.S. holder), a non-U.S. holder will generally be taxed in the same manner as a U.S. holder. In this case, a non-U.S. holder will be exempt from the withholding tax on interest discussed above, although a non-U.S. holder will be required to provide a properly executed IRS Form W-8ECI in order to claim an

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exemption from withholding. Non-U.S. holders should consult their tax advisors with respect to other U.S. tax consequences of the ownership and disposition of Notes, including the possible imposition of a branch profits tax at a rate of 30% (or a lower treaty rate) if the non-U.S. holder is a corporation.

Information reporting and backup withholding. Information returns are required to be filed with the IRS in connection with payments of interest on the Notes. Unless the non-U.S. holder complies with certification procedures to establish that the non-U.S. holder is not a United States person, information returns may also be filed with the IRS in connection with the proceeds from a sale or other disposition of a note. A non-U.S. holder may be subject to backup withholding on payments on the Notes or on the proceeds from a sale or other disposition of the Notes unless the non-U.S. holder complies with certification procedures to establish that a non-U.S. holder is not a United States person or otherwise establish an exemption. The certification procedures required to claim the exemption from withholding tax on interest described above will satisfy the certification requirements necessary to avoid backup withholding as well.

Amounts withheld under the backup withholding rules are not additional taxes and may be refunded or credited against the non-U.S. holder's U.S. federal income tax liability, provided the required information is timely furnished to the IRS.

FATCA. Provisions commonly referred to as "FATCA" impose withholding of 30% on payments of interest on the Notes and on payments of gross proceeds of sales or redemptions of the Notes to "foreign financial institutions" (which is broadly defined for this purpose and in general includes investment vehicles and financial intermediaries) and certain other non-U.S. entities unless various U.S. information reporting and due diligence requirements (generally relating to ownership by U.S. persons of interests in or accounts with those entities) have been satisfied, or an exemption applies. However, proposed Treasury Regulations (the preamble to which specifies that taxpayers are permitted to rely on them pending finalization) eliminate the withholding requirement on payments of gross proceeds of a taxable disposition (other than any amount treated as interest). Holders are encouraged to consult with their own tax advisors regarding the possible implications of FATCA on their investment in the Notes.

The discussion of U.S. federal income tax considerations set forth above is included for general information only and may not be applicable depending upon a holder's particular situation. Prospective purchasers of the Notes are urged to consult their own tax advisors with respect to the tax consequences to them of the purchase, ownership and disposition of Notes, including the tax consequences under state, local, estate, foreign and other tax laws and the possible effects of changes in U.S. or other tax laws.

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UNDERWRITING

We have entered into an underwriting agreement with Piper Sandler & Co. and Keefe, Bruyette & Woods, Inc. (collectively, the "underwriters") with respect to the Notes being offered pursuant to this prospectus supplement. Subject to certain conditions, each underwriter has agreed, severally and not jointly, to purchase the aggregate principal amount of Notes set forth next to its name in the following table.

The underwriting agreement provides that the obligations of the underwriters are subject to certain conditions precedent such as the receipt by the underwriters of officers' certificates and legal opinions and approval of certain legal matters by its counsel. The underwriting agreement provides that the underwriters have agreed, severally and not jointly, to purchase all of the Notes offered hereby if any of them are purchased. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of the non-defaulting underwriters may be increased or the underwriting agreement may be terminated under certain circumstances. We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended, and to contribute to payments that the underwriters may be required to make in respect of those liabilities.

The Notes will constitute a new class of securities with no established trading market. The underwriters have advised us that, following the completion of this offering, they currently intend to make a market in the Notes as permitted by applicable laws and regulations. However, the underwriters are not obligated to do so, and the underwriters may discontinue any market-making activities at any time without notice in their sole discretion. Accordingly, no assurance can be given as to the liquidity of the trading market for the Notes, that you will be able to sell any of the Notes held by you at a particular time or that the prices that you receive when you sell will be favorable.

The underwriters are offering the Notes offered hereby subject to their acceptance of such Notes from us and subject to prior sale. The underwriters reserve the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part.

Commission and Expenses

Notes sold by the underwriters to the public will be offered at the public offering price set forth on the cover of this prospectus supplement. If all of the Notes are not sold at their applicable initial offering prices, the underwriters may change the offering prices and the other selling terms. The offering of the Notes by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part.

The following table shows the public offering price, the underwriting discounts and commissions that we are to pay the underwriters and the proceeds, before expenses, to us in connection with this offering (expressed as a percentage of the principal amount of the Notes offered hereby).

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We estimate expenses payable by us in connection with this offering, other than, in each case, underwriting discounts and commissions, will be approximately $806,275.

We expect that delivery of the Notes will be made against payment therefor on or about October 29, which will be the second business day following the date of pricing of the Notes, or "T+2."

No Listing

The Notes will not be listed on any securities exchange or included in any automated quotation system.

No Sale of Similar Securities

We have agreed with the underwriters that for a period from the date of the underwriting agreement through and including the closing date of the offering, we and our subsidiaries will not, without the prior consent of Piper Sandler & Co. and Keefe, Bruyette & Woods, Inc., offer, sell, contract to sell or otherwise dispose of any debt securities issued or guaranteed by us or any of our subsidiaries.

Stabilization

In connection with this offering of the Notes, the underwriters may engage in overallotment, stabilizing transactions and syndicate covering transactions. Overallotment involves sales in excess of the offering size, which create a short position for the underwriters. Stabilizing transactions involve bids to purchase the Notes in the open market for the purpose of pegging, fixing or maintaining the price of the Notes. Syndicate covering transactions involve purchases of the Notes in the open market after the distribution has been completed in order to cover short positions. Stabilizing transactions and syndicate covering transactions may cause the price of the Notes to be higher than it would otherwise be in the absence of those transactions. If the underwriters engage in stabilizing or syndicate covering transactions, they may discontinue such activities at any time without notice.

Neither we nor any of the underwriters makes any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the Notes. In addition, neither we nor any of the underwriters makes any representation that the underwriters will engage in these transactions or that these transactions, once commenced, will not be discontinued without notice.

Other Activities and Relationships

The underwriters and certain of their affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The underwriters or their affiliates have, from time to time, performed, and may in the future perform, various commercial and investment banking and financial advisory services for us and our affiliates, for which they received or will receive customary fees and expenses.

In the ordinary course of their various business activities, the underwriters and certain of their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their

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customers, and such investment and securities activities may involve securities or instruments issued by us and our affiliates. If the underwriters or their affiliates have a lending relationship with us, they routinely hedge their credit exposure to us consistent with their customary risk management policies. The underwriters and their affiliates may hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities or the securities of our affiliates, including potentially the Notes offered hereby. Any such short positions could adversely affect future trading prices of the Notes offered hereby. The underwriters and their affiliates may also communicate independent investment recommendations, market color or trading ideas or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long or short positions in such securities and instruments.

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LEGAL MATTERS

The validity of the Notes offered hereby will be passed upon for OceanFirst by Luse Gorman, PC, Washington, D.C. Certain legal matters related to the offering will be passed upon for the underwriters by Freshfields US LLP, New York, New York.

EXPERTS

The consolidated financial statements of OceanFirst Financial Corp. as of December 31, 2024 and 2023 and for each of the three years in the period ended December 31, 2024, incorporated by reference in this Prospectus by reference to OceanFirst Financial Corp.'s annual report on Form 10-K for the year ended December 31, 2024, and the effectiveness of OceanFirst Financial Corp.'s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

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Prospectus

OCEANFIRST FINANCIAL CORP.

Common Stock

Preferred Stock

Depositary Shares

Debt Securities

Warrants

Units

We may offer, issue and sell, together or separately:

We will provide the specific prices and terms of these securities in one or more supplements to this prospectus at the time of offering. You should read this prospectus and the accompanying prospectus supplement carefully before you make your investment decision.

This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

Investing in our securities involves a number of risks. See "Risk Factors" on page 6 before you make your investment decision.

We may offer securities through underwriting syndicates managed or co-managed by one or more underwriters or dealers, through agents or directly to purchasers. These securities also may be resold by selling securityholders. If required, the prospectus supplement for each offering of securities will describe the plan of distribution for that offering. For general information about the distribution of securities offered, please see "Plan of Distribution" in this prospectus.

Our common stock is listed on the Nasdaq Global Select Market under the trading symbol "OCFC." Each prospectus supplement will indicate whether the securities offered thereby will be listed on any securities exchange.

These securities are not savings accounts, deposits or other obligations of any of our bank and non-bank subsidiaries and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus or any accompanying prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is October 18, 2024

TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS

This prospectus is part of an "automatic shelf" registration statement that we filed with the Securities and Exchange Commission (the "SEC") as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended (the "Securities Act"), using a "shelf" registration process. Under this process, we may sell from time to time any combination of the securities described in this prospectus.

This prospectus only provides you with a general description of the securities that we may offer. Each time we sell securities, we will provide a supplement to this prospectus that contains specific information about the terms of that offering, including the specific amounts, prices and terms of the securities offered. The prospectus supplement may also add, update or change information contained in this prospectus. You should carefully read both this prospectus, any accompanying prospectus supplement and any additional information described under the heading "Where You Can Find More Information."

This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part. You may obtain copies of those documents as described under the heading "Where You Can Find More Information."

We have not authorized anyone to provide you with any information or to make representations other than that contained in or incorporated by reference into this prospectus. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not making offers to sell the securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation.

The information in this prospectus is accurate as of the date on the front cover. You should not assume that the information contained in this prospectus is accurate as of any other date.

When used in this prospectus, the terms "OceanFirst Financial Corp.," the "Company," "we," "our" and "us" refer to OceanFirst Financial Corp. and its consolidated subsidiaries, unless otherwise specified or the context otherwise requires.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Our SEC filings are available to the public at the SEC's website at www.sec.gov.

The SEC allows us to "incorporate by reference" information into this prospectus and any accompanying prospectus supplement, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus and any accompanying prospectus supplement, except for any information superseded by information contained directly in this prospectus, any accompanying prospectus supplement, any subsequently filed document deemed incorporated by reference or any free writing prospectus prepared by or on behalf of us. This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that we have previously filed with the SEC (other than information deemed furnished and not filed in accordance with SEC rules, including Items 2.02 and 7.01 of Form 8-K).

All documents filed by us pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and before the termination of the offering also shall be deemed to be incorporated herein by reference. We are not, however, incorporating by reference any documents or portions thereof that are not deemed "filed" with the SEC, including any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K.

If requested, we will provide to each person, including any beneficial owner, to whom a prospectus is delivered, a copy of any or all of the information that has been incorporated by reference in the prospectus but not delivered with the prospectus. Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference into such documents. To obtain a copy of these filings at no cost, you may write or telephone us at the following address:

OceanFirst Financial Corp.

110 West Front Street

Red Bank, New Jersey 07701

(732) 240-4500

Attention: Investor Relations

In addition, we maintain a corporate website, www.oceanfirst.com. We make available, through our website, our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. This reference to our website is for the convenience of investors as required by the SEC and shall not be deemed to incorporate any information on the website into the registration statement.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and any accompanying prospectus supplement and any documents that we incorporated by reference contain forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act.

Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These forward-looking statements are generally identified by use of the words "believe," "expect," "intend," "anticipate," "estimate," "project," "will," "should," "may," "view," "opportunity," "potential" or similar expressions or expressions of confidence. The Company's ability to predict results or the actual effect of plans or strategies is inherently uncertain. Factors that could have a material adverse effect on the operations of the Company and its subsidiaries include, but are not limited to, the following: changes in interest rates, inflation, general economic conditions, levels of unemployment in the Company's lending area, real estate market values in the Company's lending area, potential goodwill impairment, natural disasters, potential increases to flood insurance premiums, the current or anticipated impact of military conflict, terrorism or other geopolitical events, the level of prepayments on loans and mortgage-backed securities, legislative/regulatory changes, monetary and fiscal policies of the U.S. Government, including policies of the U.S. Treasury and the Board of Governors of the Federal Reserve (the "FRB" or the "Federal Reserve"), the quality or composition of the Company's loan or investment portfolios, demand for loan products, deposit flows, the availability of low-cost funding, changes in liquidity, including the size and composition of the Company's deposit portfolio and the percentage of uninsured deposits, changes in capital management and balance sheet strategies and the ability to successfully implement such strategies, competition, demand for financial services in the Company's market area, changes in consumer spending, borrowing and saving habits, changes in accounting principles, a failure in or breach of the Company's operational or security systems or infrastructure, including cyberattacks, the failure to maintain current technologies, failure to retain or attract employees, the effect of the Company's rating under the Community Reinvestment Act, the impact of pandemics on our operations and financial results and those of our customers, the ability of OceanFirst Bank, N.A. (the "Bank") to successfully integrate acquired operations and the other risks described in this prospectus, any prospectus supplement and our reports and other documents filed with SEC. These risks and uncertainties should be considered in evaluating forward-looking statements and undue reliance should not be placed on such statements. The Company does not undertake, and specifically disclaims any obligation, to publicly release the result of any revisions that may be made to any forward-looking statements to reflect events or circumstances after the date of such statements or to reflect the occurrence of anticipated or unanticipated events.

There can be no assurance that other factors not currently anticipated by us will not materially and adversely affect our business, financial condition and results of operations. You are cautioned not to place undue reliance on any forward-looking statements made by us or on our behalf. Please take into account that forward-looking statements speak only as of the date of this prospectus or, in the case of any accompanying prospectus supplement or documents incorporated by reference, the date of any such document. Except as required by applicable law, we do not undertake any obligation to publicly correct or update any forward-looking statement.

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THE COMPANY

OceanFirst Financial Corp. is incorporated under Delaware law and serves as the holding company for the Bank. At June 30, 2024, the Company had consolidated total assets of $13.32 billion, net loans of $9.96 billion, total deposits of $9.99 billion and total stockholders' equity of $1.68 billion. The Company is subject to regulation by the FRB and the SEC. The Bank is subject to regulation and supervision by the Office of the Comptroller of the Currency and the Federal Deposit Insurance Corporation ("FDIC"). Currently, the Company does not transact any material business other than through its subsidiary, the Bank.

The Company has been the holding company for the Bank since its initial public offering in 1996. Effective January 31, 2018, the Bank converted to a national bank charter and the Company became a bank holding company. The Bank's principal business is originating loans, consisting of commercial real estate and other commercial loans, which have become a key focus of the Bank, and single-family, owner-occupied residential mortgage loans. The Bank also invests in other types of loans, including residential construction and consumer loans. The Bank primarily funds these loans by attracting retail and commercial deposits. In addition, the Bank invests in mortgage-backed securities, securities issued by the U.S. Government and agencies thereof, corporate securities and other investments permitted by applicable law and regulations. The Bank's revenues are derived principally from interest on its loans, and to a lesser extent, interest on its securities. The Bank also receives income from other products and services it offers including bankcard services, trust and asset management products and services, deposit account services, and commercial loan swap income. The Bank's primary sources of funds are deposits, principal and interest payments on loans and investments, Federal Home Loan Bank advances, and other borrowings. While scheduled payments on loans and securities are predictable sources of funds, deposit flows, loan prepayments, and loan and investment sales are greatly influenced by changes in market interest rates, competition, general economic conditions, including levels of unemployment and real estate values, and inflation.

Our principal executive office is located at 110 West Front Street, Red Bank, New Jersey 07701 and our telephone number is (732) 240-4500. We maintain a website at www.oceanfirst.com. The information on our website is not incorporated by reference in this prospectus or any accompanying prospectus supplement, and you should not consider it a part of this prospectus or any accompanying prospectus supplement.

Market Area and Competition

The Bank is a regional community bank offering a wide variety of financial accounts and services to meet the needs of customers in the communities it serves. At June 30, 2024, the Bank primarily operated its business through its headquarters located in Toms River, New Jersey, and its administrative office located in Red Bank, New Jersey. The Bank also conducts its business at 39 branch offices and various deposit production facilities located throughout central and southern New Jersey and the greater metropolitan areas of New York City and Philadelphia. The Bank also operates commercial loan production offices in New Jersey, New York City, the greater Philadelphia area, Baltimore, and Boston.

One of the largest and oldest financial institutions in New Jersey, the Bank's headquarters are approximately midway between New York City and Philadelphia. The economy in the Bank's primary market area, which represents central and southern New Jersey, is based on a mixture of service and retail trade, with other employment provided by a variety of wholesale trade, manufacturing, federal, state and local government, hospitals and utilities. The area is home to commuters working in and around New York City and Philadelphia and also includes a significant number of vacation and second homes in the communities along the New Jersey shore. In addition, the Bank provides banking services through teams located in the major metropolitan areas between Massachusetts and Virginia.

The Bank's future growth opportunities are influenced by the growth and stability of its geographic marketplace and the competitive environment. The Bank faces significant competition in making loans and

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attracting deposits. In addition, rapid technological changes and consumer preferences will continue to result in increased competition for the Bank's digital services as a number of well-funded technology-focused companies are innovating in the payments, distributed ledger, and cryptocurrency networks to disintermediate portions of the traditional banking model. The state of New Jersey, New York City, Philadelphia, Baltimore, and Boston are also attractive markets to many financial institutions. Many of the Bank's competitors are significantly larger institutions that have greater financial resources than the Bank. The Bank's competition for loans comes principally from commercial banks, savings banks, savings and loan associations, credit unions, mortgage banking companies, internet-based providers, insurance companies, private lenders, and government sponsored enterprises. Its most direct competition for deposits has historically come from commercial banks, savings banks, savings and loan associations, and credit unions. The Bank also faces competition for deposits from short-term money market funds, other corporate and government securities funds, internet-only providers, and from other financial service institutions such as brokerage firms and insurance companies. The Bank distinguishes itself from large bank competitors with teams of local financial experts in each market providing personalized accounts, extraordinary customer service and local decision-making.

Lending Activities

At June 30, 2024, the Bank had total loans outstanding of $10.02 billion, of which $6.18 billion, or 61.7% of total loans, were commercial real estate loans. The remainder of the portfolio consisted of $2.98 billion of one-to four-family residential mortgage loans, or 29.7% of total loans; $242.5 million of consumer loans, primarily home equity loans and lines of credit, or 2.4% of total loans; and $616.4 million of commercial and industrial loans, or 6.2% of total loans.

The types of loans that the Bank may originate are subject to federal and state laws and regulations. Interest rates charged by the Bank on loans are affected by the demand for such loans and the supply of money available for lending purposes and the rates offered by competitors. These factors are, in turn, affected by, among other things, economic conditions, monetary policies of the federal government, including the FRB, and legislative tax policies.

Investment Activities

The Bank views its securities portfolio primarily as a source of income and liquidity. Interest and principal payments generated from securities provide a source of liquidity to fund loans and meet short-term cash needs. The portfolio is also used to provide collateral for qualified deposits and borrowings and to manage interest rate risk.

The investment policy is overseen by the board of directors and generally limits investments to government and federal agency obligations, agency and non-agency mortgage-backed securities and municipal, corporate, and asset-backed securities. The Company's investment policy mirrors that of the Bank except that it allows for the purchase of certain other debt, preferred stock, and equity securities in limited amounts. The board of directors has delegated authority to implement the investment policy to the Company and Bank's Investment Committees under the oversight of the Asset Liability Committee. Day-to-day management of the portfolio rests with the Treasurer.

Classification of securities are determined by management at the time of purchase. If the Bank has the intent and the ability at the time of purchase to hold debt securities until maturity, they may be classified as held-to-maturity. Debt securities identified as held-to-maturity are carried at cost, adjusted for amortization of premium and accretion of discount, which are recognized as adjustments to interest income. Debt securities to be held for indefinite periods of time, but not necessarily to maturity, are classified as available-for-sale. Such debt securities are carried at an estimated fair value and unrealized gains and losses, net of tax effect, are included as a separate component of stockholders' equity.

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RISK FACTORS

Investing in our securities involves risk. See the risk factors in our most recent Annual Report on Form 10-K (together with any material changes thereto contained in subsequently filed Quarterly Reports on Form 10-Q) and those contained in our other filings with the SEC that are incorporated by reference in this prospectus and any accompanying prospectus supplement. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus and any accompanying prospectus supplement. These risks could materially affect our business, financial condition or results of operations and cause the value of our securities to decline. You could lose all or part of your investment.

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USE OF PROCEEDS

Except as otherwise set forth in any accompanying prospectus supplement, we expect to use the net proceeds from the sale of securities for general corporate purposes, including the financing of our operations, the possible repayment of indebtedness, repurchase of our common stock and possible business acquisitions.

Unless set forth in an accompanying prospectus supplement, we will not receive any proceeds if securities are sold by a selling securityholder.

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DESCRIPTION OF SECURITIES

This prospectus contains summary descriptions of the common stock, preferred stock, depositary shares, debt securities, warrants and units that may be offered and sold from time to time. These summary descriptions are not meant to be complete descriptions of each security. However, at the time of an offering and sale, this prospectus together with the accompanying prospectus supplement will contain the material terms of the securities being offered.

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DESCRIPTION OF CAPITAL STOCK

General

The following summary description of our capital stock is based on the provisions of the Delaware General Corporation Law (the "DGCL"), our certificate of incorporation, as amended, and our bylaws, as amended and restated. This description does not purport to be complete and is qualified in its entirety by reference to the full text of the DGCL, as it may be amended from time to time, and to the terms of our certificate of incorporation and bylaws, as each may be amended from time to time, which are incorporated by reference as exhibits to the registration statement of which this prospectus is a part. See "Where You Can Find More Information." As used in this "Description of Capital Stock," the terms "OceanFirst Financial Corp.," "OceanFirst," the "Company," "we," "our" and "us" refer to OceanFirst Financial Corp., a Delaware corporation, and do not, unless otherwise specified, include our subsidiaries.

Our authorized capital stock consists of 150,000,000 shares of common stock, par value $0.01 per share and 5,000,000 shares of preferred stock, par value $0.01 per share. The number of authorized shares of any class may be increased or decreased by an amendment to our certificate of incorporation proposed by our board of directors and approved by a majority of outstanding shares entitled to vote on the issue at a meeting at which a quorum exists.

Common Stock

OceanFirst's certificate of incorporation currently authorizes the issuance of up to 150,000,000 shares of common stock. As of June 30, 2024, there were (1) 62,512,415 shares of OceanFirst common stock issued and 58,481,418 shares outstanding, (2) 4,030,997 shares of OceanFirst common stock held in treasury, (3) 1,687,727 shares issuable upon the exercise of outstanding stock options to purchase shares of OceanFirst common stock granted under certain OceanFirst equity compensation plans and the equity compensation plans of acquired companies, (4) 3,045,840 options and 1,218,336 stock awards reserved for issuance under OceanFirst equity compensation plans and (5) no other shares of capital stock or equity or voting securities of OceanFirst issued, reserved for issuance or outstanding.

Preemptive Rights; Redemption Rights; Terms of Conversion; Sinking Fund and Redemption Provisions

OceanFirst common stock does not have preemptive rights, redemption rights, conversion rights, or any sinking fund or redemption provisions.

Voting Rights

The holders of OceanFirst common stock have exclusive voting rights in OceanFirst. They elect the OceanFirst board and act on other matters as are required to be presented to them under Delaware law or as are otherwise presented to them by the OceanFirst board. Generally, holders of common stock are entitled to one vote per share and do not have any right to cumulate votes in the election of directors. OceanFirst's certificate of incorporation provides that stockholders who beneficially own in excess of 10% of the then-outstanding shares of OceanFirst common stock are not entitled to any vote with respect to the shares held in excess of the 10% limit. A person or entity is deemed to beneficially own shares that are owned by an affiliate as well as persons acting in concert with such person or entity. If OceanFirst issues shares of preferred stock, holders of the preferred stock may also possess voting rights. Certain matters require an 80% stockholder vote, which is calculated after giving effect to the provision in OceanFirst's certificate of incorporation limiting voting rights as described above. OceanFirst stockholders are not permitted to act by written consent.

Liquidation Rights

In the event of OceanFirst's liquidation, dissolution or winding up, holders of common stock would be entitled to receive, after payment or provision for payment of all its debts and liabilities, all of the assets of

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OceanFirst available for distribution. If preferred stock is issued, the holders thereof may have a priority over the holders of the common stock in the event of liquidation or dissolution. In the event of any liquidation, dissolution or winding up of the Bank, OceanFirst, as the holder of 100% of the Bank's capital stock, would be entitled to receive, after payment or provision for payment of all debts and liabilities of the Bank, including all deposit accounts and accrued interest thereon, and after distribution to eligible account holders and supplemental eligible account holders of the balance in the special liquidation account established in connection with the Bank's conversion to stock form in 1996, all assets of the Bank available for distribution.

Dividend Rights

Holders of OceanFirst common stock are entitled to receive ratably such dividends as may be declared by the OceanFirst board out of legally available funds. The ability of the OceanFirst board to declare and pay dividends on OceanFirst common stock is subject to the terms of applicable Delaware law and banking regulations. If OceanFirst issues shares of preferred stock, the holders thereof may have a priority over the holders of the common stock with respect to dividends. OceanFirst's principal source of income is dividends that are declared and paid by the Bank on its capital stock. Therefore, OceanFirst's ability to pay dividends is dependent upon its receipt of dividends from the Bank. Insured depository institutions such as the Bank are prohibited from making capital distributions, including the payment of dividends, if, after making such distribution, the institution would become "undercapitalized," as such term is defined in the applicable law and regulations. In the future, any declaration and payment of cash dividends will be subject to the OceanFirst board's evaluation of OceanFirst's operating results, financial condition, future growth plans, general business and economic conditions, and tax and other relevant considerations. The payment of cash dividends by OceanFirst in the future will also be subject to certain other legal and regulatory limitations and ongoing review by OceanFirst's banking regulators.

Restrictions on Ownership

Banking laws impose notice, approval and ongoing regulatory requirements on any stockholder or other party that seeks to acquire direct or indirect "control" of an FDIC-insured depository institution. These laws include the Bank Holding Company Act of 1956, as amended (the "BHC Act") and the Change in Bank Control Act of 1978, as amended (the "Change in Bank Control Act"). Among other things, these laws require regulatory filings by a stockholder or other party that seeks to acquire direct or indirect "control" of an FDIC-insured depository institution.

The determination whether an investor "controls" a depository institution is based on all of the facts and circumstances surrounding the investment. OceanFirst is a bank holding company and therefore the BHC Act would require any "bank holding company" (as defined in the BHC Act) to obtain prior approval of the Federal Reserve Board before acquiring more than 5% of OceanFirst common stock. Any person (other than a bank holding company) is required to provide prior notice to the FRB before acquiring 10% or more of OceanFirst common stock under the Change in Bank Control Act. Ownership by affiliated parties, or parties acting in concert, is typically aggregated for these purposes. Any person (other than an individual) who (a) owns, controls or has the power to vote 25% or more of any class of OceanFirst's voting securities; (b) has the ability to elect or appoint a majority of the OceanFirst board; or (c) otherwise has the ability to exercise a "controlling influence" over OceanFirst, is subject to regulation as a bank holding company under the BHC Act.

Preferred Stock

OceanFirst's certificate of incorporation authorizes the OceanFirst board of directors, without further stockholder action, to issue up to 5,000,000 shares of preferred stock. OceanFirst's certificate of incorporation further authorizes the OceanFirst board, subject to any limitations prescribed by law, to provide for the issuance of the shares of preferred stock in series, and by filing a certificate pursuant to the applicable law of the State of Delaware, to establish from time to time the number of shares to be included in each such series, and to fix the

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designation, powers, preferences and rights of the shares of each such series and any qualifications, limitations or restrictions thereof. As of June 30, 2024, there were 57,370 shares of OceanFirst 7.0% Series A Non-Cumulative, perpetual preferred stock ("Series A Preferred Stock") outstanding, which have the terms set forth below. Preferred stock may be issued with preferences and designations as the OceanFirst board may from time to time determine. The OceanFirst board may, without stockholder approval, issue shares of preferred stock with voting, dividend, liquidation and conversion rights that could dilute the voting power of the holders of OceanFirst common stock and may assist management in impeding an unfriendly takeover or attempted change in control.

Series A Preferred Stock

Ranking

Shares of the Series A Preferred Stock rank, with respect to the payment of dividends and distributions upon liquidation, dissolution, or winding-up:

Dividends

Dividends on shares of the Series A Preferred Stock are discretionary and not cumulative. Holders of the Series A Preferred Stock are entitled to receive, if, when, and as declared by the board of directors or a duly authorized committee of board of directors, out of legally available assets, non-cumulative cash dividends quarterly in arrears on February 15, May 15, August 15 and November 15 of each year (each such date being referred to herein as a "dividend payment date") based on a liquidation preference of $1,000 per share (equivalent to $25 per depositary share).

If declared by the board of directors or a duly authorized committee of the board of directors, dividends accrue from and including the original issue date to, but excluding, May 15, 2025 or the date of earlier redemption (the "fixed rate period"), at a rate of 7.00% per annum. If declared by the board of directors or a duly authorized committee of the board of directors, dividends will accrue from and including May 15, 2025 to, but excluding, the date of earlier redemption (the "floating rate period"), at a floating rate per annum equal to the Benchmark rate (which is expected to be Three-Month Term SOFR) plus a spread of 684.5 basis points. Notwithstanding the foregoing, if the Benchmark rate is less than zero, the Benchmark rate shall be deemed to be zero.

Dividends on shares of the Series A Preferred Stock are not cumulative. Accordingly, if the board of directors or a duly authorized committee of the board of directors does not declare a full dividend on the Series A Preferred Stock payable in respect of any dividend period before the related dividend payment date, such dividend will not accrue and OceanFirst will have no obligation to pay a dividend for that dividend period on the dividend payment date or at any future time, whether or not dividends on the Series A Preferred Stock are declared for any future dividend period.

Priority of Dividends

The Series A Preferred Stock will rank junior as to payment of dividends to any class or series of the preferred stock that OceanFirst may issue in the future that is expressly stated to be senior to the Series A

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Preferred Stock. If at any time the OceanFirst does not pay, on the applicable dividend payment date, accrued dividends on any shares that rank in priority to the Series A Preferred Stock with respect to dividends, OceanFirst may not pay any dividends on the Series A Preferred Stock or repurchase, redeem, or otherwise acquire for consideration any shares of Series A Preferred Stock until OceanFirst has paid, or set aside for payment, the full amount of the unpaid dividends on the shares that rank in priority with respect to dividends that must, under the terms of such shares, be paid before OceanFirst may pay dividends on, repurchase, redeem, or otherwise acquire for consideration, the Series A Preferred Stock. As of the date hereof, there are no other shares of preferred stock issued and outstanding.

So long as any share of Series A Preferred Stock remains outstanding, unless the full dividends for the most recently completed dividend period have been declared and paid, or set aside for payment, on all outstanding shares of Series A Preferred Stock:

Notwithstanding the foregoing, if dividends are not paid in full, or set aside for payment in full, on any dividend payment date upon the shares of the Series A Preferred Stock and any shares of parity stock, all dividends declared upon the Series A Preferred Stock and all such parity stock payable on such dividend payment date will be declared pro rata in proportion to the respective amounts of undeclared and unpaid dividends on the Series A Preferred Stock and all parity stock payable on such dividend payment date. To the extent a dividend period with respect to any parity stock coincides with more than one dividend period with respect to the Series A Preferred Stock for purposes of the immediately preceding sentence, OceanFirst's board of directors will treat such dividend period as two or more consecutive dividend periods, none of which coincides with more than one dividend period with respect to the Series A Preferred Stock, or will treat such dividend period(s) with respect to any parity stock and dividend period(s) with respect to the Series A Preferred Stock for purposes of the

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immediately preceding sentence in any other manner that it deems to be fair and equitable to achieve ratable payments on such dividend parity stock and the Series A Preferred Stock. To the extent a dividend period with respect to the Series A Preferred Stock coincides with more than one dividend period with respect to any parity stock, for purposes of the first sentence of this paragraph, the board of directors will treat such dividend period as two or more consecutive dividend periods, none of which coincides with more than one dividend period with respect to such parity stock, or will treat such dividend period(s) with respect to the Series A Preferred Stock and dividend period(s) with respect to any parity stock for purposes of the first sentence of this paragraph in any other manner that it deems to be fair and equitable to achieve ratable payments of dividends on the Series A Preferred Stock and such parity stock. For the purposes of this paragraph, the term "dividend period" as used with respect to any parity stock means such dividend periods as are provided for in the terms of such parity stock.

Subject to the foregoing, dividends (payable in cash, stock, or otherwise) may be declared and paid on junior stock, which includes common stock, from time to time out of any assets legally available for such payment, and the holders of Series A Preferred Stock or parity stock will not be entitled to participate in any such dividend.

Redemption

The Series A Preferred Stock is perpetual and has no maturity date and is not subject to any mandatory redemption, sinking fund, or other similar provisions. The holders of the Series A Preferred Stock will not have any right to require the redemption or repurchase of their shares of Series A Preferred Stock.

OceanFirst may, at its option, redeem the Series A Preferred Stock (1) in whole or in part, from time to time, on May 15, 2025, or on any dividend payment date on or after May 15, 2025, or (2) in whole but not in part at any time within 90 days following a "regulatory capital treatment event," in each case at a redemption price equal to $1,000 per share (equivalent to $25 per depositary share), plus the per share amount of any declared and unpaid dividends, without accumulation of any undeclared dividends, on the Series A Preferred Stock to, but excluding, the date fixed for redemption (the "redemption date"). Any declared but unpaid dividends payable on a redemption date that occur subsequent to the applicable dividend record date will not be paid to the holder entitled to receive the redemption price on the redemption date, but rather will be paid to the holder of record of the redeemed shares on such record date relating to the applicable dividend payment date. Investors should not expect OceanFirst to redeem the Series A Preferred Stock on or after the date it becomes redeemable at OceanFirst's option.

If shares of the Series A Preferred Stock are to be redeemed, the notice of redemption will be given to the holders of record of the Series A Preferred Stock to be redeemed, by first class mail, postage prepaid, addressed to the holders of record of such shares to be redeemed at their respective last addresses appearing on OceanFirst's stock register not less than 30 days nor more than 60 days before the date fixed for redemption thereof (provided that, if the shares of Series A Preferred Stock are held in book-entry form through The Depository Trust Company ("DTC") may give such notice in any manner permitted by DTC). Each notice of redemption will include a statement setting forth:

If notice of redemption of any shares of Series A Preferred Stock has been duly given and if the funds necessary for such redemption have been set aside by us for the benefit of the holders of any shares of Series A Preferred Stock so called for redemption, then, on and after the redemption date, dividends will cease to accrue

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on such shares of Series A Preferred Stock, such shares of Series A Preferred Stock will no longer be deemed outstanding, and all rights of the holders of such shares will terminate, except the right to receive the redemption price, without interest.

In case of any redemption of only part of the shares of the Series A Preferred Stock at the time outstanding, the shares to be redeemed will be selected pro rata, by lot, or in such other manner as OceanFirst may determine to be equitable and permitted by DTC and the rules of any national securities exchange on which the Series A Preferred Stock is listed.

Liquidation Rights

If OceanFirst voluntarily or involuntarily liquidates, dissolves, or winds up its affairs, holders of the Series A Preferred Stock are entitled to receive out of OceanFirst's assets available for distribution to stockholders, after satisfaction of liabilities and obligations to creditors, if any, and subject to the rights of holders of any shares of capital stock then outstanding ranking senior to or on parity with the Series A Preferred Stock with respect to distributions upon the voluntary or involuntary liquidation, dissolution, or winding-up of OceanFirst's business and affairs, including the Series A Preferred Stock, and before OceanFirst makes any distribution or payment out of its assets to the holders of common stock or any other class or series of capital stock ranking junior to the Series A Preferred Stock with respect to distributions upon liquidation, dissolution, or winding-up, an amount per share equal to the liquidation preference of $1,000 per share plus any declared and unpaid dividends prior to the payment of the liquidating distribution (but without any amount in respect of dividends that have not been declared before the date of payment of the liquidating distribution). After payment of the full amount of the liquidating distribution described above, the holders of the Series A Preferred Stock will not be entitled to any further participation in any distribution of OceanFirst's assets.

In any such distribution, if OceanFirst's assets are not sufficient to pay the liquidation preference in full to all holders of Series A Preferred Stock and all holders of any shares of capital stock ranking as to any such liquidating distribution on parity with the Series A Preferred Stock, including the Series A Preferred Stock, the amounts paid to the holders of Series A Preferred Stock and to such other shares will be paid pro rata in accordance with the respective aggregate liquidation preferences of those holders. In any such distribution, the "liquidation preference" of any holder of preferred stock means the amount otherwise payable to such holder in such distribution (assuming no limitation on OceanFirst's assets available for such distribution), including any declared but unpaid dividends (and, in the case of any holder of stock other than the Series A Preferred Stock and on which dividends accrue on a cumulative basis, an amount equal to any unpaid, accrued, cumulative dividends, whether or not declared, as applicable). If the liquidation preference per share of Series A Preferred Stock has been paid in full to all holders of Series A Preferred Stock and the liquidation preference per share of any other capital stock ranking on parity with the Series A Preferred Stock as to liquidation rights has been paid in full, the holders of common stock or any other capital stock ranking, as to liquidation rights, junior to the Series A Preferred Stock will be entitled to receive all the remaining assets according to their respective rights and preferences.

The Series A Preferred Stock may be fully subordinate to interests held by the U.S. government if the Company enters into a receivership, insolvency, liquidation, or similar proceeding, including a proceeding under the "orderly liquidation authority" provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010.

Neither the sale, conveyance, exchange, or transfer of all or substantially all of OceanFirst's assets or business, nor the consolidation or merger by OceanFirst with or into any other entity or by another entity with or into OceanFirst, whether for cash, securities, or other property, individually or as part of a series of transactions, will constitute a liquidation, dissolution, or winding-up of its affairs.

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Because OceanFirst is a holding company, the rights and the rights of OceanFirst's creditors and stockholders, including the holders of the Series A Preferred Stock, to participate in any distribution of assets of any of OceanFirst's subsidiaries upon that subsidiary's liquidation, dissolution, reorganization or winding-up or otherwise would be subject to the prior claims of that subsidiary's creditors, except to the extent that OceanFirst is a creditor with recognized claims against the subsidiary.

Holders of the Series A Preferred Stock are subordinate to all of OceanFirst's indebtedness and to other non-equity claims on OceanFirst and its assets, including if OceanFirst enters into a receivership, insolvency, liquidation or similar proceeding. In addition, holders of the Series A Preferred Stock (and of depositary shares representing the Series A Preferred Stock) may be fully subordinated to interests held by the U.S. government if OceanFirst enters into a receivership, insolvency, liquidation or similar proceeding.

Voting Rights

Except as provided below and as determined by OceanFirst's board of directors or a duly authorized committee of the board of directors or as otherwise expressly required by law, the holders of the Series A Preferred Stock will have no voting rights.

Whenever dividends on any shares of the Series A Preferred Stock, or any parity stock upon which similar voting rights have been conferred ("special voting preferred stock"), have not been declared and paid in an aggregate amount equal to the amount of dividends payable on the Series A Preferred Stock for the equivalent of six or more quarterly dividend periods, whether or not consecutive (which refer to as a "nonpayment"), the holders of the Series A Preferred Stock, voting together as a class with holders of any special voting preferred stock then outstanding, will be entitled to vote (based on respective liquidation preferences) for the election of two additional members of the board of directors (which are referred to as the "preferred directors"); provided that the board of directors will at no time include more than two preferred directors; provided, further, that the election of any such preferred directors may not cause OceanFirst to violate any corporate governance requirement of The Nasdaq Stock Market LLC (or any other exchange on which OceanFirst's securities may be listed). In that event, the number of directors on the board of directors will automatically increase by two and, at the request of any holder of Series A Preferred Stock, a special meeting of the holders of Series A Preferred Stock and such special voting preferred stock, including the Series A Preferred Stock, for which dividends have not been paid will be called for the election of the two directors (unless such request is received less than 90 days before the date fixed for the next annual or special meeting of stockholders, in which event such election shall be held at such next annual or special meeting of stockholders), followed by such election at each subsequent annual meeting. These voting rights will continue until full dividends have been paid (or declared and a sum sufficient for the payment of such dividends has been set aside for payment) on the Series A Preferred Stock and such special voting preferred stock for four dividend periods following the nonpayment.

If and when full dividends have been paid (or declared and a sum sufficient for the payment of such dividends has been set aside for payment) for at least four dividend periods following a nonpayment on the Series A Preferred Stock and such special voting preferred stock, the holders of the Series A Preferred Stock and such special voting preferred stock will be divested of the foregoing voting rights (subject to revesting in the event of each subsequent nonpayment) and the term of office of each preferred director so elected will terminate and the number of directors on OceanFirst's board of directors will automatically decrease by two.

Any preferred director may be removed at any time without cause by the holders of a majority of the outstanding shares of the Series A Preferred Stock and such special voting preferred stock, voting together as a class, when they have the voting rights described above. So long as a nonpayment continues, any vacancy in the office of a preferred director (other than before the initial election of the preferred directors) may be filled by the written consent of the preferred director remaining in office, or if none remains in office, by a vote of the holders of a majority of the outstanding shares of Series A Preferred Stock and such special voting preferred stock, voting together as a class, to serve until the next annual meeting of stockholders; provided that the filling of any

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such vacancy may not cause OceanFirst to violate any corporate governance requirement of The Nasdaq Stock Market LLC (or any other exchange on which OceanFirst's securities may be listed). The preferred directors will each be entitled to one vote per director on any matter on which OceanFirst's directors are entitled to vote.

Under regulations adopted by the Federal Reserve, if the holders of one or more series of preferred stock are or become entitled to vote for the election of directors, such series entitled to vote for the same director(s) will be deemed a class of voting securities and a company holding 25% or more of the series, or 10% or more if it otherwise exercises a "controlling influence" over OceanFirst, will be subject to regulation as a bank holding company under the BHC Act. In addition, if the series is/are deemed to be a class of voting securities, any other bank holding company will be required to obtain the prior approval of the Federal Reserve under the BHC Act to acquire or retain more than 5% of that series. Any other person (other than a bank holding company) will be required to obtain the non-objection of the Federal Reserve under the Change in Bank Control Act, to acquire or retain 10% or more of that series. While OceanFirst does not believe the shares of Series A Preferred Stock are considered "voting securities" currently, holders of such stock should consult their own counsel with regard to regulatory implications. A holder or group of holders may also be deemed to control OceanFirst if they own one-third or more of OceanFirst's total equity.

So long as any shares of Series A Preferred Stock remain outstanding, in addition to any other vote or consent of stockholders required by law or OceanFirst's certificate of incorporation, as amended, the affirmative vote or consent of the holders of at least two-thirds of all of the then-outstanding shares of Series A Preferred Stock entitled to vote thereon, voting separately as a single class, will be required to:

When determining the application of the voting rights described in this section, the authorization, creation, and issuance, or an increase in the authorized or issued amount, of junior stock or any class or series of capital stock that by its terms expressly provides that it ranks on parity with the Series A Preferred Stock with respect to the payment of dividends (whether such dividends are cumulative or non-cumulative) and as to distributions upon OceanFirst's liquidation, dissolution, or winding-up, or any securities convertible into or exchangeable or exercisable for junior stock or any class or series of capital stock, will not be deemed to materially and adversely affect the special powers, preferences, privileges, or rights, and will not require the affirmative vote or consent of, the holders of any outstanding shares of Series A Preferred Stock.

The foregoing voting provisions will not apply if, at or before the time when the act with respect to which such vote would otherwise be required will be effected, all outstanding shares of Series A Preferred Stock will

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have been redeemed or called for redemption upon proper notice and sufficient funds will have been set aside by OceanFirst for the benefit of the holders of the Series A Preferred Stock to effect such redemption.

Depositary Shares

General

Each depositary share represents a 1/40th interest in a share of the Series A Preferred Stock and will be evidenced by depositary receipts. Subject to the terms of the deposit agreement, the depositary shares will be entitled to all of the powers, preferences, and special rights of the Series A Preferred Stock, as applicable, in proportion to the applicable fraction of a share of Series A Preferred Stock those depositary shares represent. As of June 30, 2024, there were 2,294,800 depositary shares issued.

Dividends and Other Distributions

Each dividend payable on a depositary share will be in an amount equal to 1/40th of the dividend declared and payable on each share of Series A Preferred Stock.

The depositary will distribute all dividends and other cash distributions received on the Series A Preferred Stock to the holders of record of the depositary receipts in proportion to the number of depositary shares held by each holder. If OceanFirst makes a distribution other than in cash, the depositary will distribute property received by it to the holders of record of the depositary receipts in proportion to the number of depositary shares held by each holder, unless the depositary determines that this distribution is not feasible, in which case the depositary may, with OceanFirst's approval, adopt a method of distribution that it deems practicable, including the sale of the property and distribution of the net proceeds of that sale to the holders of the depositary receipts.

If the calculation of a dividend or other cash distribution results in an amount that is a fraction of a cent and that fraction is equal to or greater than $0.005, the depositary will round that amount up to the next highest whole cent and will request that OceanFirst pay the resulting additional amount to the depositary for the relevant dividend or other cash distribution. If the fractional amount is less than $0.005, the depositary will disregard that fractional amount and it will be added to and be treated as part of the next succeeding distribution.

Record dates for the payment of dividends and other matters relating to the depositary shares will be the same as the corresponding record dates for the Series A Preferred Stock.

The amount paid as dividends or otherwise distributable by the depositary with respect to the depositary shares or the underlying Series A Preferred Stock will be reduced by any amounts required to be withheld by OceanFirst or the depositary on account of taxes or other governmental charges. The depositary may refuse to make any payment or distribution, or any transfer, exchange, or withdrawal of any depositary shares or the shares of the Series A Preferred Stock, until such taxes or other governmental charges are paid.

Liquidation Preference

In the event of liquidation, dissolution, or winding-up, a holder of depositary shares will receive the fraction of the liquidation preference accorded each share of underlying Series A Preferred Stock represented by the depositary shares.

Neither the sale, conveyance, exchange, or transfer of all or substantially all of OceanFirst's assets or business, nor the consolidation or merger by OceanFirst with or into any other entity or by another entity with or into the OceanFirst, whether for cash, securities, or other property, individually or as part of a series of transactions, will constitute a liquidation, dissolution, or winding-up of OceanFirst's affairs.

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Redemption of Depositary Shares

If OceanFirst redeems the Series A Preferred Stock, in whole or in part, depositary shares also will be redeemed with the proceeds received by the depositary from the redemption of the Series A Preferred Stock held by the depositary. The redemption price per depositary share will be 1/40th of the redemption price per share payable with respect to the Series A Preferred Stock (or $25 per depositary share), plus 1/40th of the per share amount of any declared and unpaid dividends, without accumulation of any undeclared dividends, on the Series A Preferred Stock to, but excluding, the redemption date.

If OceanFirst redeems shares of the Series A Preferred Stock held by the depositary, the depositary will redeem, as of the same redemption date, the number of depositary shares representing those shares of the Series A Preferred Stock so redeemed. If OceanFirst redeems less than all of the outstanding depositary shares, the depositary shares to be redeemed will be selected either pro rata or by lot or in such other manner as OceanFirst may determine to be fair and equitable. The depositary will provide notice of redemption to record holders of the depositary receipts not less than 30 days and not more than 60 days before the date fixed for redemption of the Series A Preferred Stock and the related depositary shares.

Voting

Because each depositary share represents a 1/40th ownership interest in a share of Series A Preferred Stock, holders of depositary receipts will be entitled to vote 1/40th of a vote per depositary share under those limited circumstances in which holders of the Series A Preferred Stock are entitled to vote.

When the depositary receives notice of any meeting at which the holders of the Series A Preferred Stock are entitled to vote, the depositary will, if requested in writing and provided with all necessary information, provide the information contained in the notice to the record holders of the depositary shares relating to the Series A Preferred Stock. Each record holder of the depositary shares on the record date, which will be the same date as the record date for the Series A Preferred Stock, may instruct the depositary to vote the amount of the Series A Preferred Stock represented by the holder's depositary shares. To the extent possible, the depositary will vote or cause to be voted the amount of the Series A Preferred Stock represented by depositary shares in accordance with the instructions it receives. OceanFirst will agree to take all reasonable actions that the depositary determines are necessary to enable the depositary to vote as instructed. If the depositary does not receive specific instructions from the holders of any depositary shares representing the Series A Preferred Stock, it will abstain from voting with respect to such shares (but may, at its discretion, appear at the meeting with respect to such shares unless directed to the contrary).

Anti-Takeover Effects of Provisions of the Certificate of Incorporation, Bylaws and Other Agreements

Set forth below is a summary of the provisions of the Certificate of Incorporation and the Bylaws that could delay or prevent a change in control of the Company. The following description is only a summary and it is qualified by reference to the Certificate of Incorporation, the Bylaws and relevant provisions of the DGCL.

Blank Check Preferred Stock

The Certificate of Incorporation authorizes 5,0000,000 undesignated shares of preferred stock and permits our board of directors to issue preferred stock with rights or preferences that could impede the success of any attempt to change control of the Company. For example, our board of directors, without stockholder approval, may create or issue preferred stock with conversion rights that could adversely affect the voting power of the holders of our common stock as well as rights to such preferred stock, in connection with implementing a stockholder rights plan. This provision may have a potential anti-takeover effect because the issuance of such preferred stock may delay or prevent a change of control of the Company. Furthermore, shares of preferred stock, if any are issued, may have other rights, including economic rights, senior to common stock, and, as a result, the issuance thereof could depress the market price of our common stock.

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No Cumulative Voting

The Certificate of Incorporation and the Bylaws do not provide holders of our common stock cumulative voting rights in the election of directors. The absence of cumulative voting could have the effect of preventing stockholders holding a minority of our shares of common stock from obtaining representation on our board of directors. The absence of cumulative voting might also, under certain circumstances, render more difficult or discourage a merger, tender offer or proxy contest favored by a majority of our stockholders, the assumption of control by a holder of a large block of our stock or the removal of incumbent management.

Advance Notice Requirements for Stockholder Proposals and Director Nominees

The Bylaws require stockholders seeking to make nominations of candidates for election as directors or to bring other business before a meeting of our stockholders to provide timely notice of their intent in writing. To be timely, a stockholder's notice must be delivered to the Secretary at our principal executive offices not less than 90 days before the date of the annual meeting; provided, however, that if less than 100 days' notice or prior public disclosure of the date of the meeting is given or made to stockholders, notice by the stockholder to be timely must be received not later than the close of business on the 10th day following the day on which such notice of the date of the annual meeting was mailed or such public disclosure was made. A stockholder's notice must include certain information about the stockholder and the nominee or proposal as specified in the Bylaws. These advance notice provisions may restrict the ability of the stockholders to make nominations for directors at or bring business before a meeting of the Company's stockholders.

Business Combinations with an Interested Stockholder

OceanFirst is also subject to Section 203 of the DGCL. Section 203 prohibits the Company from engaging in any business combination (as defined in Section 203) with an "interested stockholder" for a period of three years subsequent to the date on which the stockholder became an interested stockholder unless:

For purposes of Section 203, an "interested stockholder" is defined as an entity or person beneficially owning 15% or more of the Company's outstanding voting stock, based on voting power, and any entity or person affiliated with or controlling or controlled by such an entity or person. A "business combination" includes mergers, asset sales and other transactions resulting in financial benefit to a stockholder.

Section 203 could prohibit or delay mergers or other takeover or change of control attempts with respect to the Company and, accordingly, may discourage attempts that might result in a premium over the market price for the shares held by stockholders.

In addition, OceanFirst's certificate of incorporation provides that a business combination with an interested stockholder requires the affirmative vote of the holders of at least 80% of the voting power of the then-outstanding shares of voting stock of OceanFirst, subject to the 10% voting restriction. The super-majority vote is not required for a business combination with an interested stockholder that is approved by a majority of disinterested directors or meets certain consideration value requirements. An interested stockholder is defined as: (1) any person who beneficially owns 10% or more of the voting power of OceanFirst's voting stock; (2) an

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affiliate or associate of OceanFirst who, at any time within the two-year period before the date in question, was the beneficial owner of 10% or more of the voting power of the then outstanding voting stock of OceanFirst; or (3) an assignee of shares of voting stock that were at any time within the two-year period immediately before the date in question beneficially owned by any interested stockholder.

Such provisions may have the effect of deterring hostile takeovers or delaying changes in control of management or the Company.

Listing

Our common stock is listed on the Nasdaq Global Select Market under the symbol "OCFC." Our depositary shares are listed on the Nasdaq Global Select Market under the symbol "OCFCP."

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Broadridge Corporation Issuer Solutions, Inc.

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DESCRIPTION OF DEPOSITARY SHARES

We may offer depositary receipts representing fractional shares of our preferred stock, rather than full shares of preferred stock. The shares of preferred stock represented by depositary shares will be deposited under a depositary agreement between us and a bank or trust company that meets certain requirements and is selected by us (the "Bank Depositary"). Each owner of a depositary share will be entitled to all the rights and preferences of the preferred stock represented by the depositary share.

The description in an accompanying prospectus supplement of any depositary shares we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable depositary agreement, which will be filed with the SEC if we offer depositary shares. For more information on how you can obtain copies of any depositary agreement if we offer depositary shares, see "Where You Can Find More Information." We urge you to read the applicable depositary agreement and any accompanying prospectus supplement in their entirety.

Dividends and Other Distributions

If we pay a cash distribution or dividend on a series of preferred stock represented by depositary shares, the Bank Depositary will distribute such dividends to the record holders of such depositary shares. If the distributions are in property other than cash, the Bank Depositary will distribute the property to the record holders of the depositary shares. However, if the Bank Depositary determines that it is not feasible to make the distribution of property, the Bank Depositary may, with our approval, sell such property and distribute the net proceeds from such sale to the record holders of the depositary shares.

Redemption of Depositary Shares

If we redeem a series of preferred stock represented by depositary shares, the Bank Depositary will redeem the depositary shares from the proceeds received by the Bank Depositary in connection with the redemption. The redemption price per depositary share will equal the applicable fraction of the redemption price per share of the preferred stock. If fewer than all the depositary shares are redeemed, the depositary shares to be redeemed will be selected by lot or pro rata as the Bank Depositary may determine.

Voting the Preferred Stock

Upon receipt of notice of any meeting at which the holders of the preferred stock represented by depositary shares are entitled to vote, the Bank Depositary will mail the notice to the record holders of the depositary shares relating to such preferred stock. Each record holder of these depositary shares on the record date, which will be the same date as the record date for the preferred stock, may instruct the Bank Depositary as to how to vote the preferred stock represented by such holder's depositary shares. The Bank Depositary will endeavor, insofar as practicable, to vote the amount of the preferred stock represented by such depositary shares in accordance with such instructions, and we will take all action that the Bank Depositary deems necessary to enable the Bank Depositary to do so. The Bank Depositary will abstain from voting shares of the preferred stock to the extent it does not receive specific instructions from the holders of depositary shares representing such preferred stock.

Amendment and Termination of the Depositary Agreement

The form of depositary receipt evidencing the depositary shares and any provision of the depositary agreement may be amended by agreement between the Bank Depositary and us. However, any amendment that materially and adversely alters the rights of the holders of depositary shares will not be effective unless such amendment has been approved by the holders of at least a majority of the depositary shares then outstanding. The depositary agreement may be terminated by the Bank Depositary or us only if (1) all outstanding depositary shares have been redeemed or (2) there has been a final distribution in respect of the preferred stock in connection with any liquidation, dissolution or winding up of our company and such distribution has been distributed to the holders of depositary receipts.

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Withdrawal of Preferred Stock

Except as may be provided otherwise in an accompanying prospectus supplement, upon surrender of depositary receipts at the principal office of the Bank Depositary, subject to the terms of the depositary agreement, the owner of the depositary shares may demand delivery of the number of whole shares of preferred stock and all money and other property, if any, represented by those depositary shares. Partial shares of preferred stock will not be issued. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the number of depositary shares representing the number of whole shares of preferred stock to be withdrawn, the Bank Depositary will deliver to such holder at the same time a new depositary receipt evidencing the excess number of depositary shares. Holders of withdrawn preferred stock may not thereafter deposit those shares under the depositary agreement or receive depositary receipts evidencing depositary shares therefor.

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DESCRIPTION OF DEBT SECURITIES

We may offer debt securities in one or more series, which may be senior debt securities or subordinated debt securities and that may be convertible into another security.

The following description briefly sets forth certain general terms and provisions of the debt securities. The particular terms of the debt securities offered by any prospectus supplement and the extent, if any, to which the following general terms and provisions may apply to the debt securities, will be described in an accompanying prospectus supplement. Unless otherwise specified in an accompanying prospectus supplement, our debt securities will be issued in one or more series under an indenture to be entered into between us and Wilmington Trust, National Association, as trustee, or such other trustee named therein. A form of the indenture is attached as an exhibit to the registration statement of which this prospectus forms a part. The terms of the debt securities will include those set forth in the indenture and those made a part of the indenture by the Trust Indenture Act of 1939 ("TIA"). You should read the summary below, any accompanying prospectus supplement and the provisions of the indenture in their entirety before investing in our debt securities.

The aggregate principal amount of debt securities that may be issued under the indenture is unlimited. The prospectus supplement relating to any series of debt securities that we may offer will contain the specific terms of the debt securities. These terms may include, among others, the following:

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General

We may sell the debt securities, including original issue discount securities, at par or at a substantial discount below their stated principal amount. Unless we inform you otherwise in a prospectus supplement, we may issue additional debt securities of a particular series without the consent of the holders of the debt securities of such series or any other series outstanding at the time of issuance. Any such additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of securities under the indenture.

We will describe in an accompanying prospectus supplement any other special considerations for any debt securities we sell that are denominated in a currency or currency unit other than U.S. dollars. In addition, debt securities may be issued where the amount of principal and/or interest payable is determined by reference to one or more currency exchange rates, commodity prices, equity indices or other factors. Holders of such securities may receive a principal amount or a payment of interest that is greater than or less than the amount of principal or interest otherwise payable on such dates, depending upon the value of the applicable currencies, commodities, equity indices or other factors. Information as to the methods for determining the amount of principal or interest, if any, payable on any date, and the currencies, commodities, equity indices or other factors to which the amount payable on such date is linked will be described in an accompanying prospectus supplement.

United States federal income tax consequences and special considerations, if any, applicable to any such series will be described in an accompanying prospectus supplement.

We expect most debt securities to be issued in fully registered form without coupons and in minimum denominations of $1,000 and any integral multiple in excess thereof. Subject to the limitations provided in the indenture and in an accompanying prospectus supplement, debt securities that are issued in registered form may be transferred or exchanged at the designated corporate trust office of the trustee, without the payment of any service charge, other than any tax or other governmental charge payable in connection therewith.

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Global Securities

Unless we inform you otherwise in an accompanying prospectus supplement, the debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in an accompanying prospectus supplement. Unless and until a global security is exchanged in whole or in part for the individual debt securities, a global security may not be transferred except as a whole by the depositary for such global security to a nominee of such depositary or by a nominee of such depositary to such depositary or another nominee of such depositary or by such depositary or any such nominee to a successor of such depositary or a nominee of such successor.

Governing Law

The indenture and the debt securities shall be construed in accordance with and governed by the laws of the State of New York.

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DESCRIPTION OF WARRANTS

We may issue warrants to purchase shares of our common stock, shares of preferred stock or our debt securities. We may issue warrants independently or together with other securities, and they may be attached to or separate from the other securities. Each series of warrants will be issued under a separate warrant agreement that we will enter into with a bank or trust company, as warrant agent, as detailed in an accompanying prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation, or agency or trust relationship, with you.

The prospectus supplement relating to a particular issue of warrants will describe the terms of those warrants, including, when applicable:

After warrants expire they will become void. The prospectus supplement may provide for the adjustment of the exercise price of the warrants.

Warrants may be exercised at the appropriate office of the warrant agent or any other office indicated in an accompanying prospectus supplement. Before the exercise of warrants, holders will not have any of the rights of holders of the securities purchasable upon exercise and will not be entitled to payments made to holders of those securities.

The description in an accompanying prospectus supplement of any warrants we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable warrant agreement, which will be filed with the SEC if we offer warrants. For more information on how you can obtain copies of any warrant agreement if we offer warrants, see "Where You Can Find More Information." We urge you to read the applicable warrant agreement and any accompanying prospectus supplement in their entirety.

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DESCRIPTION OF UNITS

We may issue units comprised of one or more of the other securities described in this prospectus in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security.

The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The applicable prospectus supplement may describe:

The description in an accompanying prospectus supplement of any unit we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable unit, which will be filed with the SEC if we offer units. For more information on how you can obtain copies of any unit we may offer, see "Where You Can Find More Information." We urge you to read the applicable purchase contract or applicable purchase unit and any accompanying prospectus supplement in their entirety.

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SELLING SECURITYHOLDERS

Information about selling securityholders, where applicable, will be set forth in a prospectus supplement, in a post-effective amendment or in filings we make with the SEC under the Exchange Act that are incorporated by reference into this prospectus.

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PLAN OF DISTRIBUTION

We or the selling securityholders may sell the securities being offered hereby in one or more of the following ways from time to time:

In addition, we may enter into derivative or hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. In connection with such a transaction, the third parties may sell securities covered by and pursuant to this prospectus and any accompanying prospectus supplement. If so, the third party may use securities borrowed from us or others to settle such sales and may use securities received from us to close out any related short positions. We may also loan or pledge securities covered by this prospectus and any accompanying prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and any accompanying prospectus supplement.

We will identify the specific plan of distribution in a prospectus supplement, including:

Underwriters, dealers and agents

If we use underwriters in an offering, we will execute an underwriting agreement with such underwriters and will specify the name of each underwriter and the terms of the transaction (including any underwriting discounts and other terms constituting compensation of the underwriters and any dealers) in a prospectus supplement. If we use an underwriting syndicate, the managing underwriter(s) will be specified on the cover of the prospectus supplement. If we use underwriters for a sale of securities, the underwriters will acquire the securities for their own accounts. The underwriters may resell the securities from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time. Unless otherwise set forth in the prospectus supplement, the obligations of the underwriters to purchase the offered securities will be subject to conditions precedent and the underwriters will be obligated to purchase all of the offered securities if any are purchased.

If agents are used in an offering, the names of the agents and the terms of the agency will be specified in a prospectus supplement. Unless otherwise indicated in a prospectus supplement, the agents will act on a best-efforts basis for the period of their appointment.

If dealers are used in an offering, we may sell the securities to the dealers as principals. The dealers then may resell the securities to the public at varying prices that they determine at the time of resale. The names of the dealers and the terms of the transaction will be specified in a prospectus supplement.

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If agents are used in an offering, the names of the agents and the terms of the agency will be specified in a prospectus supplement. Unless otherwise indicated in a prospectus supplement, the agents will act on a best-efforts basis for the period of their appointment.

Dealers and agents named in a prospectus supplement may be underwriters as defined in the Securities Act of 1933 and any discounts or commissions they receive from us and any profit on their resale of the securities may be treated as underwriting discounts and commissions under the Securities Act of 1933. We will identify in the applicable prospectus supplement any underwriters, dealers or agents and will describe their compensation. We may have agreements with the underwriters, dealers and agents to indemnify them against specified civil liabilities, including liabilities under the Securities Act of 1933.

Underwriters, dealers or agents and their associates may engage in other transactions with and perform other services for us in the ordinary course of business.

If so indicated in a prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by institutional investors to purchase securities pursuant to contracts providing for payment and delivery on a future date. We may enter contracts with commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutional investors. The obligations of any institutional investor will be subject to the condition that its purchase of the offered securities will not be illegal at the time of delivery. The underwriters and other agents will not be responsible for the validity or performance of contracts.

Direct sales

We may sell securities directly to one or more purchasers without using underwriters or agents.

At-the-market offerings

We may also sell the securities offered by any applicable prospectus supplement in "at-the-market offerings" within the meaning of Rule 415 of the Securities Act of 1933, to or through a market maker or into an existing trading market, on an exchange or otherwise.

Trading markets and listing of securities

Unless otherwise specified in the applicable prospectus supplement, each class or series of securities will be a new issue with no established trading market, other than our common stock, which is listed on the Nasdaq Global Select Market. We may elect to list any other class or series of securities on any exchange, but we are not obligated to do so. It is possible that one or more underwriters may make a market in a class or series of securities, but the underwriters will not be obligated to do so and may discontinue any market making at any time without notice. We cannot give any assurance as to the liquidity of the trading market for any of the securities.

Stabilization activities

In connection with an offering, an underwriter may purchase and sell securities in the open market. These transactions may include short sales, stabilizing transactions and purchases to cover positions created by short sales. Short sales involve the sale by the underwriters of a greater number of securities than they are required to purchase in the offering. "Covered" short sales are sales made in an amount not greater than the underwriters' option to purchase additional securities, if any, from us in the offering. If the underwriters have an over-allotment option to purchase additional securities from us, the underwriters may close out any covered short position by either exercising their over-allotment option or purchasing securities in the open market. In determining the source of securities to close out the covered short position, the underwriters may consider, among other things, the price of securities available for purchase in the open market as compared to the price at which they may purchase securities through the over-allotment option. "Naked" short sales are any sales in excess of such option or where the underwriters do not have an over-allotment option. The underwriters must close out any naked short

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position by purchasing securities in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the securities in the open market after pricing that could adversely affect investors who purchase in the offering.

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LEGAL MATTERS

Unless otherwise indicated in any accompanying prospectus supplement, Luse Gorman, PC, Washington, DC, will provide opinions regarding the authorization and validity of the securities. Luse Gorman, PC may also provide opinions regarding certain other matters. Any underwriters will be advised about legal matters by their own counsel, which will be named in an accompanying prospectus supplement.

EXPERTS

The consolidated financial statements of OceanFirst Financial Corp. as of December 31, 2023 and 2022, and for each of the two years in the period ended December 31, 2023, incorporated by reference in this Prospectus, and the effectiveness of OceanFirst Financial Corp.'s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

The consolidated financial statements of OceanFirst Financial Corp. for the year ended December 31, 2021 included in our Annual Report on Form 10-K for the year ended December 31, 2023, have been incorporated by reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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$185,000,000

6.375% Fixed-to-Floating Rate Subordinated Notes due 2035

PROSPECTUS SUPPLEMENT

Joint Book-running Managers

October 27, 2025