Supplemental Prospectus (Form 424B5)

Filed pursuant to Rule 424(b)(5)
Registration No. 333-288361

PROSPECTUS SUPPLEMENT

(To the Prospectus dated July 3, 2025)

Bakkt Holdings, Inc.

(to be renamed Bakkt, Inc.)

Up to $300,000,000

Class A Common Stock

We have entered into a Sales Agreement, dated January 16, 2026 (the "Sales Agreement"), with The Benchmark Company, LLC, Virtu Americas LLC, Clear Street LLC, Cohen & Company Capital Markets, a division of Cohen & Company Securities, LLC, Macquarie Capital (USA) Inc., Rosenblatt Securities Inc. and Roth Capital Partners, LLC (each, a "Sales Agent" and together, the "Sales Agents"), relating to the sale of shares of our Class A common stock, $0.0001 par value per share ("Common Stock"), offered by this prospectus supplement and the accompanying prospectus. In accordance with the terms of the Sales Agreement, we may offer and sell shares of our Common Stock having an aggregate offering price of up to $300,000,000 from time to time.

Sales of shares of our Common Stock under this prospectus supplement and the accompanying prospectus, if any, may be made by any method deemed to be an "at the market offering" as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended (the "Securities Act"), including sales made in ordinary brokers' transactions on the New York Stock Exchange (the "NYSE") or otherwise at market prices prevailing at the time of the sale, at prices related to prevailing market prices or at negotiated prices and block trades. The Sales Agents are not required to sell any specific number or dollar amount of shares of our Common Stock. The Sales Agents have agreed to use their commercially reasonable efforts to sell on our behalf all of the shares of Common Stock requested to be sold by us, consistent with their normal trading and sales practices, on mutually agreed terms among the Sales Agents and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement. We also may sell shares to one or more of the Sales Agents as principals for their own accounts, at a price agreed upon at the time of sale. If we sell shares to a Sales Agent as principal, we will enter into a separate terms agreement with the applicable Sales Agent setting forth the terms of such transaction, and we intend to describe this agreement in a separate pricing supplement.

Each of the Sales Agents will be entitled to compensation under the terms of the Sales Agreement at a commission rate equal to up to 3% of the gross sales price per share sold. In connection with the sale of Common Stock on our behalf, each of the Sales Agents will be deemed to be an "underwriter" within the meaning of the Securities Act, and the compensation of each of the Sales Agents will be deemed to be underwriting commissions or discounts. The shares of our Common Stock will be sold through only one Sales Agent on any given day. We have agreed to provide indemnification and contribution to the Sales Agents with respect to certain liabilities, including liabilities under the Securities Act. See "Plan of Distribution" for additional information regarding compensation to be paid to each of the Sales Agents.

The offering of shares of our Common Stock pursuant to the Sales Agreement will terminate upon the earlier of (1) the sale of shares of our Common Stock having an aggregate sales price of $300,000,000 pursuant to the Sales Agreement or (2) the termination of the Sales Agreement in accordance with its terms.

The net proceeds from any sales under this prospectus will be used as described under the section entitled "Use of Proceeds." The proceeds we receive from sales of shares of our Common Stock, if any, will depend on the number of shares actually sold and the offering price of such shares, which shall be agreed upon at the time of sale.

Our Common Stock is traded on the NYSE under the symbol "BKKT." On January 16, 2026, the last reported sales price of our Common Stock on the NYSE was $21.41 per share.

Investing in our Common Stock involves risks. You should read carefully and consider "Risk Factors" included in this prospectus supplement on page S-4 and in our accompanying prospectus beginning on page 6 and in the documents that are incorporated by reference into this prospectus supplement before investing in our Common Stock.

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

The date of this prospectus supplement is January 20, 2026.

TABLE OF CONTENTS

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PROSPECTUS SUPPLEMENT

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PROSPECTUS

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which describes the terms of this offering of our Common Stock and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part consists of a prospectus dated July 3, 2025, included in the registration statement on Form S-3 (No. 333-288361). Since the accompanying prospectus provides general information about us, some of the information may not apply to this offering. This prospectus supplement describes the specific details regarding this offering. Generally, when we refer to the "prospectus," we are referring to both parts of this document. Additional information is incorporated by reference in this prospectus supplement. If information in this prospectus supplement is inconsistent with the accompanying prospectus, you should rely on this prospectus supplement. You should read this prospectus supplement, the accompanying prospectus and any information incorporated by reference before you make any investment decision.

Neither we nor the Sales Agents are making an offer to sell the Common Stock in jurisdictions where the offer or sale is not permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offer and sale of our Common Stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about and observe any restrictions relating to the offering of the securities and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute an offer of, or an invitation to purchase, any shares of Common Stock in any jurisdiction in which such offer or invitation would be unlawful.

You should rely only on information contained in this prospectus supplement, the accompanying prospectus and the documents we incorporate by reference in this prospectus supplement. We have not authorized anyone to provide you with information that is different from that contained in this prospectus supplement. We are not offering to sell or seeking offers to buy shares of Common Stock in jurisdictions where offers and sales are not permitted. The information contained in this prospectus supplement and the accompanying prospectus supplement is accurate only as of their respective dates, regardless of the time of delivery of this prospectus supplement or of any sale of our Common Stock.

Unless otherwise mentioned or unless the context requires otherwise, all references in this prospectus supplement to the "Company," "we," "us," "our" and "Bakkt" refer to Bakkt Holdings, Inc., a Delaware corporation, and its consolidated subsidiaries.

This prospectus supplement 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 supplement is a part, and you may obtain copies of those documents as described below under the section entitled "Incorporation of Certain Information by Reference."

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION

This prospectus supplement and the accompanying prospectus, including documents incorporated by reference herein and therein, contain forward-looking statements within the meaning of the federal securities laws, which statements involve substantial risks and uncertainties. Forward-looking statements generally relate to future events or our future financial or operating performance. You can identify forward-looking statements because they contain words such as "anticipate," "believe," "continue," "could," "estimate," "expect," "intends," "may," "might," "plan," "possible," "potential," "predict," "project," "should," "will," "would," the negative of such terms, and other similar expressions that are intended to identify forward-looking statements. These forward-looking statements are based on management's current expectations, assumptions, hopes, beliefs, intentions and strategies regarding future events and are based on currently available information as to the outcome and timing of future events. We caution you that these forward-looking statements are subject to all of the risks and uncertainties, most of which are difficult to predict and many of which are beyond our control, incident to our business. Forward-looking statements included or incorporated by reference into this prospectus supplement and the accompanying prospectus may include, for example, statements about:

These forward-looking statements are based on information available as of the date they were made and reflect management's expectations, forecasts and assumptions as of such date, and involve a number of judgments, known and/or unknown risks and uncertainties. Accordingly, forward-looking statements should not be relied upon as representing our views as of any subsequent date. We do not undertake any obligation to update any forward-looking statement to reflect events or circumstances after the date they were made, whether as a result of new information, future events or otherwise, except as may be required under applicable law.

You should not place undue reliance on these forward-looking statements. Should one or more of a number of known and unknown risks and uncertainties materialize, or should any of our assumptions prove incorrect, our actual results or performance may be materially different from those expressed or implied by these forward-looking statements. Some factors that could cause actual results to differ include, but are not limited to:

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RISK FACTORS

An investment in our Common Stock involves a high degree of risk. Before investing in our Common Stock, you should carefully read this entire prospectus supplement, the accompanying prospectus and the documents incorporated herein and therein, including the matters set forth under this "Risk Factors" section and any risk factors described in any amendments or supplements to this prospectus supplement, the accompanying prospectus and in the documents incorporated by reference herein, including our most recent Annual Report on Form 10-K for the year ended December 31, 2024, our quarterly reports on Form 10-Q for the quarter ended March 31, 2025, the quarter ended June 30, 2025 and the quarter ended September 30, 2025, and the risks regarding our adoption of the Investment Policy set forth in Exhibit 99.1 to our Current Report on Form 8-K, filed with the SEC on June 10, 2025. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations.

In connection with the forward-looking statements that appear in this prospectus supplement and the accompanying prospectus, you should also carefully review the cautionary statement referred to under "Forward-Looking Statements" in this prospectus supplement.

Risks Related to this Offering

If you purchase shares of Common Stock in this offering, you may experience immediate dilution of your investment.

The offering price per share of Common Stock in this offering may exceed the net tangible book value per share of our Common Stock outstanding prior to this offering. Assuming that an aggregate of 14,278,914 shares of our Common Stock are sold during the term of the Sales Agreement with the Sales Agent at a price of $21.01 per share, the last reported sale price of our Common Stock on the NYSE on January 14, 2026, for aggregate net proceeds of approximately $288.7 million, after deducting commissions and estimated aggregate offering expenses payable by us, you will experience immediate dilution of approximately $11.86 per share, representing the difference between our as adjusted net tangible book value per share as of September 30, 2025 after giving effect to this offering and the assumed offering price. The exercise of outstanding options and warrants, and vesting and settlement of restricted stock units, performance-based restricted stock units and other equity incentive awards that may be settled into shares of our Common Stock, and issuance of additional shares of our Common Stock or other securities that are convertible into or exchangeable or exercisable for shares of our Common Stock from time to time, including pursuant to equity-incentive plans, as consideration for acquisitions or otherwise, may result in further dilution of your investment. See the section entitled "Dilution" below for a more detailed illustration of the dilution you would incur if you participate in this offering.

The actual number of shares of Common Stock we will issue under the Sales Agreement and the aggregate net proceeds resulting from such issuances, at any one time or in total, is uncertain.

Subject to certain limitations in the Sales Agreement and compliance with applicable law, we have the discretion to deliver a placement notice to the Sales Agents at any time throughout the term of the Sales Agreement. The number and per share price of the shares of Common Stock that are sold by the Sales Agents after delivering a placement notice will fluctuate based upon a number of factors, including the market price per share of our Common Stock during the sales period, any limits we set with the Sales Agents in the applicable placement notice and the demand for our Common Stock. Because the number of shares that are sold through the Sales Agents and the price per share of each share of Common Stock sold in this offering will fluctuate based on the market price per share of our Common Stock during the sales period, it is not possible at this stage to predict the number of shares of our Common Stock that will be ultimately issued or the aggregate net proceeds to be raised in connection with sales under this offering.

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The Common Stock offered hereby will be sold in "at the market offerings," and investors who buy shares of our Common Stock at different times will likely pay different prices.

Investors who purchase shares of our Common Stock in this offering at different times will likely pay different prices, and so may experience different levels of dilution and different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and numbers of shares of our Common Stock sold, and there is no minimum or maximum sales price. Investors may experience a decline in the value of their shares of our Common Stock as a result of share sales made at prices lower than the prices they paid.

We may issue Common Stock as consideration for strategic acquisitions or investments, including the DTR Acquisition, which may result in dilution of your investment.

We may issue shares of our Common Stock or other securities from time to time as consideration for, or to finance, future acquisitions, investments, debt-for-equity exchanges or for other capital needs. We cannot predict the size of future issuances of our Common Stock or the effect, if any, that future sales and issuances of Common Stock would have on the market price of our Common Stock. If any such acquisition or investment is significant, the number of shares of Common Stock or the number or aggregate principal amount, as the case may be, of other securities that we may issue may in turn be substantial and may result in additional dilution to our shareholders. We may also grant registration rights covering shares of our Common Stock or other securities that we may issue in connection with any such acquisitions and investments.

For example, on January 11, 2026, Bakkt Opco Holdings, LLC ("Opco"), a Delaware limited liability company and wholly owned subsidiary of the Company, entered into a Share Purchase Agreement (the "Purchase Agreement") by and among Opco, the Company, DTR, and Akshay Naheta (Mr. Naheta or the "Seller"). Pursuant to the terms and subject to the conditions set forth in the Purchase Agreement, the Company will acquire DTR (the "DTR Acquisition") by issuing to the DTR Holders (as defined below) the DTR Acquisition Share Consideration to the Seller and other beneficial owners of DTR shares (the "DTR Holders"). The DTR Acquisition is subject to the approval of the Company's shareholders. If the DTR Acquisition is approved by the Company's shareholders, the DTR Acquisition Share Consideration will be issued and your investment will be diluted.

Our management will have broad discretion over the use of the net proceeds from this offering, you may not agree with how we use the proceeds, and the proceeds may not be invested successfully.

We currently intend to use the net proceeds from this Offering for working capital and for general corporate purposes. Our management will have broad discretion over the use and investment of these net proceeds and could spend the proceeds in ways that do not improve our results of operations or enhance the value of our Common Stock. Accordingly, you will have to rely upon the judgment of our management with respect to the use of these net proceeds, with only limited information concerning management's specific intentions. You will not have the opportunity, as part of your investment decision, to assess whether we will use the net proceeds from this offering appropriately. If we do not invest or apply the net proceeds, if any, from this offering or our existing cash in ways that enhance stockholder value, we may fail to achieve expected results, which could cause the price per share of our Common Stock to decline.

We may need additional capital, and any additional capital we seek may not be available in the amount or at the time we need it, or on terms that would be acceptable to us.

We may need to raise funds in the future to execute our business plan. We may seek to raise additional capital to fund or expand our business, pursue strategic investments, and take advantage of financing or other opportunities that we believe to be in our best interests and the interests of our stockholders. Additional capital may be raised through the sale of common or preferred equity or convertible debt securities, entry into debt facilities or other third-party funding arrangements. The sale of equity and convertible debt securities may result

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in dilution to our stockholders and those securities may have rights senior to those of our Common Stock. Agreements entered into in connection with such capital raising activities could contain covenants that would restrict our operations or require us to relinquish certain rights. Additional capital may not be available on reasonable terms, or at all. If we cannot timely raise any needed funds, we may be forced to reduce our operating expenses, which could adversely affect our ability to implement our long-term strategic roadmap and grow our business.

The market price of our securities may be volatile.

The trading market for our securities has in the past been and could in the future be impacted by market volatility. During the 12 months ended January 16, 2026, the market price of our Common Stock has ranged from a high of $49.79 per share to a low of $6.81 per share. This market volatility could reduce the market price of our securities without regard to our operating performance. In addition, the trading price of our Common Stock could change significantly in response to actual or anticipated variations in our quarterly operating results, announcements by us or our competitors, factors affecting the digital asset industry generally, changes in national or regional economic conditions, changes in securities analysts' estimates for us or our competitors' or industry's future performance or general market conditions, making it more difficult for our securities to be sold at a favorable price or at all. The market price of our Common Stock could also be reduced by general market price declines or market volatility in the future or future declines or volatility in the prices of stocks for companies in our industry.

Because we do not anticipate paying any cash dividends on our capital stock in the foreseeable future, capital appreciation, if any, will be your sole source of gain.

We have never declared or paid cash dividends on our capital stock. We anticipate that we will retain our earnings, if any, for future growth and therefore do not anticipate paying cash dividends in the future. As a result, only appreciation of the price of our Common Stock will provide a return to stockholders.

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USE OF PROCEEDS

We may issue and sell shares of our Common Stock having aggregate sales proceeds of up to $300,000,000 from time to time pursuant to the Sales Agreement. The amount of proceeds from this offering will depend upon the number of shares of our Common Stock sold and the market price at which they are sold. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. There can be no assurance that we will sell any shares of Common Stock under or fully utilize the Sales Agreement as a source of financing.

We currently intend to use the net proceeds from this offering, if any, for working capital and for general corporate purposes.

As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses of the proceeds from this offering. Accordingly, we will retain broad discretion over the use of such proceeds. Pending the use of the net proceeds from this offering as described above, we intend to invest the net proceeds in short-term, investment-grade securities.

DIVIDEND POLICY

We have never declared or paid cash dividends on our capital stock. We currently intend to retain our future earnings, if any, for use in our business and therefore do not anticipate paying cash dividends in the foreseeable future. Payment of future dividends, if any, will be at the discretion of our Board of Directors after taking into account various factors, including our financial condition, operating results, current and anticipated cash needs and plans for expansion.

CAPITALIZATION

The Sales Agreement provides that we may offer and sell up to 14,278,914 shares of our Common Stock from time to time through the Sales Agents for the offer and sale of such Common Stock. The table below assumes that we will sell 14,278,914 shares available under the Sales Agreement at a price of $21.01 per share (the last reported sale price per share of our Common Stock on January 14, 2026) but there is no guarantee that there will be any sales of our Common Stock pursuant to this prospectus supplement and the accompanying prospectus. Actual sales, if any, of our Common Stock under this prospectus supplement and the accompanying prospectus may be less than as set forth in the table below. In addition, the price per share of any such sale may be greater or less than $21.01, depending on the market price of our Common Stock at the time of any such sale.

The following table sets forth our capitalization as of September 30, 2025:

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The number of shares of our Common Stock to be outstanding immediately after this offering is based on 25,529,359 shares of Common Stock outstanding as of January 14, 2026. This figure excludes, as of that date, 285,615 shares of Common Stock reserved for the exercise of publicly traded warrants currently listed on the NYSE; 2,404,317 shares of Common Stock reserved for outstanding equity awards and the remaining pool of incentive equity available under the Omnibus Incentive Plan; 1,954,866 shares of Common Stock for the exercise of a one-time grant of options to select members of management to purchase shares of the Company's Common Stock; 1,153,200 shares of Common Stock reserved for the exercise of Class 1 Warrants; 864,650 shares of Common Stock reserved for the exercise of Class 2 Warrants; 815,282 shares of Common Stock reserved for the exercise of an inducement grant provided to Akshay Naheta in connection with his appointment as an officer of the Company; and the DTR Acquisition Share Consideration.

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DESCRIPTION OF THE COMMON STOCK

The material terms and provisions of our Common Stock are described in the "Description of Securities" attached as Exhibit 99.1 to our Current Report on Form 8-K12B filed on November 3, 2025 and are incorporated herein by reference.

DILUTION

If you purchase shares of Common Stock in this offering, your ownership interest will be diluted to the extent of the difference between the offering price per share of Common Stock and the as adjusted net tangible book value per share of our Common Stock after this offering. Our net tangible book value as of September 30, 2025 was approximately $58.4 million, or $2.47 per share of the aggregate of our outstanding shares of Common Stock and our outstanding shares of Class V Common Stock. "Net tangible book value" is total assets minus the sum of liabilities, goodwill, intangible assets and operating leases. "Net tangible book value per share" is net tangible book value divided by the total number of shares of Common Stock and Class V Common Stock outstanding.

After giving effect to the assumed sale by us of an aggregate of $300,000,000 in shares of Common Stock in this offering at an assumed offering price of $21.01 per share, which was the last reported sale price of our Common Stock on the NYSE on January 14, 2026, and after deducting estimated commissions and offering expenses payable by us, our as adjusted net tangible book value as of September 30, 2025 would have been approximately $347.1 million, or $9.15 per share of Common Stock. This represents an immediate increase in the net tangible book value of $6.68 per share to our existing stockholders and an immediate dilution in the net tangible book value of $11.86 per share of Common Stock to investors purchasing Common Stock in this offering. The following table illustrates this calculation on a per share basis:

The table above assumes for illustrative purposes that an aggregate of $300,000,000 in shares of our Common Stock are sold at a price of $21.01 per share, which was the last reported sale price of our Common Stock on the NYSE on January 14, 2026. The shares sold in this offering, if any, will be sold from time to time at various prices. An increase of $1.00 per share in the price at which the shares of our Common Stock are sold from the assumed offering price of $21.01 per share shown in the table above, assuming all of our Common Stock in the aggregate amount of $300,000,000 is sold at that price, would increase our as adjusted net tangible book value per share after the offering to $9.52 per share and would increase the dilution in the net tangible book value per share to investors purchasing Common Stock in this offering to $12.49 per share. A decrease of $1.00 per share in the price at which the shares of our Common Stock are sold from the assumed offering price of $21.01 per share shown in the table above, assuming all of our Common Stock in the aggregate amount of $300,000,000 is sold at that price, would decrease our net tangible book value per share after the offering to $8.79 per share and would decrease the dilution in the net tangible book value per share to investors purchasing Common Stock in this offering to $11.22 per share.

The number of shares of our Common Stock to be outstanding immediately after this offering is based on 25,529,359 shares of Common Stock outstanding as of January 14, 2026. This figure excludes, as of that date, 285,615 shares of Common Stock reserved for the exercise of publicly traded warrants currently listed on the

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NYSE; 2,404,317 shares of Common Stock reserved for outstanding equity awards and the remaining pool of incentive equity available under the Omnibus Incentive Plan; 1,954,866 shares of Common Stock for the exercise of a one-time grant of options to select members of management to purchase shares of the Company's Common Stock; 1,153,200 shares of Common Stock reserved for the exercise of Class 1 Warrants; 864,650 shares of Common Stock reserved for the exercise of Class 2 Warrants; 815,282 shares of Common Stock reserved for the exercise of an inducement grant provided to Akshay Naheta in connection with his appointment as an officer of the Company; and the DTR Acquisition Share Consideration.

To the extent that any outstanding options or warrants are exercised, restricted stock units or performance-based restricted stock units and vest and are settled, and other equity incentive awards that may be settled into shares of our Common Stock are issued in the future at a price less than the public offering price, there will be further dilution to the investors.

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MATERIAL UNITED STATES FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERS OF OUR COMMON STOCK

This section summarizes certain United States federal income tax consequences of the ownership and disposition of our Common Stock issued pursuant to this offering by a non-U.S. holder. You are a non-U.S. holder if you are, for United States federal income tax purposes:

This section does not consider the specific facts and circumstances that may be relevant to a particular non-U.S. holder and does not address the treatment of a non-U.S. holder under the laws of any state, local or foreign taxing jurisdiction. This section is based on the tax laws of the United States, including the Internal Revenue Code of 1986, as amended (the "Code"), existing and proposed regulations, and administrative and judicial interpretations, all as currently in effect. These laws are subject to change, possibly on a retroactive basis.

If an entity or arrangement that is treated as a partnership for United States federal income tax purposes holds our Common Stock, the United States federal income tax treatment of a partner will generally depend on the status of the partner and the tax treatment of the partnership. A partner in a partnership holding our Common Stock should consult its tax advisor with regard to the United States federal income tax treatment of an investment in our Common Stock.

PROSPECTIVE INVESTORS SHOULD CONSULT THEIR TAX ADVISORS REGARDING THE PARTICULAR U.S. FEDERAL INCOME TAX CONSEQUENCES TO THEM OF ACQUIRING, OWNING AND DISPOSING OF OUR COMMON STOCK, AS WELL AS ANY TAX CONSEQUENCES ARISING UNDER ANY STATE, LOCAL OR NON-U.S. TAX LAWS AND ANY U.S. FEDERAL NON-INCOME TAX LAWS, OR UNDER ANY APPLICABLE INCOME TAX TREATY.

Dividends

As described in the section titled "Dividend Policy," we do not anticipate declaring or paying any dividends to holders of our Common Stock in the foreseeable future. However, if we make a distribution of cash or other property (other than certain distributions of our stock) in respect of our Common Stock, the distribution generally will be treated as a dividend to the extent of our current or accumulated earnings and profits, as determined under United States federal income tax principles. Any portion of a distribution that exceeds our current and accumulated earnings and profits will generally be treated first as a tax-free return of capital, on a share-by-share basis, to the extent of your tax basis in our Common Stock (and will reduce your basis in such Common Stock), and, to the extent such portion exceeds your tax basis in our Common Stock, the excess will be treated as gain from the taxable disposition of our Common stock, the tax treatment of which is discussed below under "Gain on Disposition of our Common Stock."

Except as described below, dividends paid to you on our Common Stock are subject to withholding of United States federal income tax at a 30% rate or at a lower rate if you are eligible for the benefits of an income tax treaty that provides for a lower rate. Even if you are eligible for a lower treaty rate, the financial institution or other withholding agent will generally be required to withhold at a 30% rate (rather than the lower treaty rate) on dividend payments to you, unless you have furnished to the financial institution or other withholding agent:

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If you are eligible for a reduced rate of United States withholding tax under a tax treaty, you may generally obtain a refund of any amounts withheld in excess of that rate by filing a refund claim with the United States IRS.

If dividends paid to you are "effectively connected" with your conduct of a trade or business within the United States, and, if required by a tax treaty, the dividends are attributable to a permanent establishment or fixed base that you maintain in the United States, withholding agents are generally not required to withhold tax from the dividends, provided that you have furnished to the withholding agent a valid IRS Form W-8ECI or an acceptable substitute form upon which you represent, under penalties of perjury, that:

"Effectively connected" dividends are taxed at rates applicable to United States persons.

If you are a corporate non-U.S. holder for U.S. federal income tax purposes, "effectively connected" dividends that you receive may, under certain circumstances, be subject to an additional "branch profits tax" at a 30% rate or at a lower rate if you are eligible for the benefits of an income tax treaty that provides for a lower rate.

Gain on Disposition of our Common Stock

You generally will not be subject to United States federal income tax on gain that you recognize on a disposition of our Common Stock unless:

If the gain from the taxable disposition of shares of our Common Stock is effectively connected with your conduct of a trade or business in the United States (and, if required by a tax treaty, the gain is attributable to a permanent establishment or fixed base that you maintain in the United States), you will be subject to tax on the net gain derived from the sale at rates applicable to United States persons. If you are a corporate non-U.S. holder

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for U.S. federal income tax purposes, "effectively connected" gains that you recognize may also, under certain circumstances, be subject to an additional "branch profits tax" at a 30% rate or at a lower rate if you are eligible for the benefits of an income tax treaty that provides for a lower rate. If you are an individual non-U.S. holder described in the second bullet point immediately above, you will be subject to a flat 30% tax (unless an applicable income tax treaty provides otherwise) on the gain derived from the sale, which may be offset by United States source capital losses, even though you are not considered a resident of the United States.

If the third bullet point above applies to you, then gain you realize will be subject to U.S. federal income tax at generally applicable U.S. federal income tax rates. In addition, a buyer may be required to withhold U.S. federal income tax at a rate of 15% of the amount realized upon such disposition. We will be a United States real property holding corporation at any time that the fair market value of our "United States real property interests," as defined in the Code and applicable Treasury Regulations, equals or exceeds 50% of the aggregate fair market value of our worldwide real property interests and our other assets used or held for use in a trade or business (all as determined for the U.S. federal income tax purposes). We believe that we are not, and do not anticipate becoming in the foreseeable future, a United States real property holding corporation.

FATCA Withholding

Pursuant to sections 1471 through 1474 of the Code, commonly known as the Foreign Account Tax Compliance Act ("FATCA"), a 30% withholding tax ("FATCA withholding") may be imposed on certain payments to you or to certain foreign financial institutions, investment funds and other non-U.S. persons receiving payments on your behalf if you or such persons fail to comply with certain information reporting requirements. Payments of dividends that you receive in respect of our Common Stock could be affected by this withholding if you are subject to the FATCA information reporting requirements and fail to comply with them or if you hold our Common Stock through a non-U.S. person (e.g., a foreign bank or broker) that fails to comply with these requirements (even if payments to you would not otherwise have been subject to FATCA withholding). FATCA withholding was scheduled to apply to gross proceeds from the disposition of property that produces U.S.-source dividends (such as our Common Stock) beginning on January 1, 2019. However, Treasury Regulations were proposed which, if finalized in their present form, would eliminate the U.S. federal withholding tax of 30% applicable to the gross proceeds of a sale or other disposition of our Common Stock. Although the proposed Treasury Regulations are not final, taxpayers may generally rely on the proposed Treasury Regulations until final Treasury Regulations are issued. You should consult your own tax advisors regarding the relevant U.S. law and other official guidance on FATCA withholding.

Information Reporting and Backup Withholding

Withholding agents are generally required to report payments of dividends on our Common Stock on IRS Form 1042-S even if the payments are exempt from withholding. You are otherwise generally exempt from backup withholding and information reporting requirements with respect to dividend payments and the payment of the proceeds from the sale of our Common Stock effected at a United States office of a broker provided that either (i) you have furnished a valid IRS Form W-8 or other documentation upon which the payor or broker may rely to treat the payments as made to a non-United States person, or (ii) you otherwise establish an exemption.

Payment of the proceeds from the sale of our Common Stock effected at a foreign office of a broker generally will not be subject to information reporting or backup withholding. However, a sale effected at a foreign office of a broker could be subject to information reporting in the same manner as a sale within the United States (and in certain cases may be subject to backup withholding as well) if (i) the broker has certain connections to the United States, (ii) the proceeds or confirmation are sent to the United States or (iii) the sale has certain other specified connections with the United States.

Backup withholding is not an additional tax. The amount of any backup withholding from a payment to a non-U.S. holder will be allowed as a credit against such non-U.S. holder's U.S. federal income tax liability and may entitle such holder to a refund, provided that the required information is timely furnished to the IRS.

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PLAN OF DISTRIBUTION

General

We have entered into a Sales Agreement with The Benchmark Company, LLC, Virtu Americas LLC, Clear Street LLC, Cohen & Company Capital Markets, a division of Cohen & Company Securities, LLC, Macquarie Capital (USA) Inc., Rosenblatt Securities Inc. and Roth Capital Partners, LLC, pursuant to which we may issue and sell from time to time shares of our Common Stock having an aggregate offering price of up to $300,000,000 through the Sales Agents, acting as our agents, or directly to one or more Sales Agents, acting as principals. A copy of the Sales Agreement will be filed as an exhibit to a Current Report on Form 8-K and will be incorporated by reference into this prospectus supplement. If we sell our Common Stock to any Sales Agent, acting as principal, we will enter into a separate agreement setting forth the terms of such transaction and, to the extent required by applicable law, we will describe this agreement in a separate prospectus supplement or pricing supplement.

Sales, if any, of our Common Stock under the Sales Agreement may be made in sales deemed to be "at-the-market offerings" as defined in Rule 415(a)(4) promulgated under the Securities Act, including by means of ordinary brokers' transactions, to or through a market maker, on or through the NYSE or any other market venue where the securities may be traded, in the over-the-counter market, in privately negotiated transactions (including block transactions), or through a combination of any such methods of sale. The Sales Agents may also sell our Common Stock by any other method permitted by law.

The shares of Common Stock may be sold at market prices prevailing at the time of sale, at prices related to such prevailing market prices or at negotiated prices. We cannot predict the number of shares of our Common Stock that we may sell under the Sales Agreement on the NYSE or any other trading market for our Common Stock in the United States, or if any Common Stock will be sold at all.

Upon receipt of written instructions from us and subject to the terms and conditions of the Sales Agreement, the applicable Sales Agent will use its commercially reasonable efforts consistent with its normal sales and trading practices to sell on our behalf the shares of our Common Stock. We will instruct a Sales Agent as to the maximum amount of Common Stock to be sold by such Sales Agent pursuant to such instructions. We may instruct such Sales Agent not to sell any Common Stock if the sales cannot be effected at or above the price designated by us in any such instruction. We or any Sales Agent, with respect to itself only, may suspend the offering of our Common Stock by notifying the other party.

A Sales Agent will provide to us written confirmation no later than the opening of the trading day on the NYSE following the trading day on which shares of Common Stock are sold under the Sales Agreement. Each confirmation will include the number of shares of Common Stock sold on the preceding day, the net proceeds to us and the compensation payable by us to the applicable Sales Agent. We will report at least quarterly the number of shares of Common Stock sold through the Sales Agents under the Sales Agreement, the net proceeds to us (before expenses) and the compensation paid by us to the Sales Agents in connection with the sales of shares of Common Stock.

We will pay each Sales Agent commissions for its services in acting as agent and/or principal in the sale of our Common Stock. Each Sales Agent will be entitled to compensation that will not exceed, but may be lower than, a commission rate of up to 3% of the gross sales price per share of Common Stock sold to or through such agent under the Sales Agreement. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. We have also agreed to reimburse the Sales Agents for certain specified expenses, including the fees and expenses of their legal counsel in an amount not to exceed $75,000 in connection with the execution of the Sales Agreement and $10,000 per calendar quarter thereafter and certain ongoing expenses. We estimate that the total expenses for the offering, excluding compensation and reimbursements payable to the Sales Agents under the terms of the Sales Agreement, will be approximately $2,300,000.

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Settlement of any sales of Common Stock will occur on the first trading day following the date on which such sales were made, or on some other date that is agreed upon by us and the Sales Agents in connection with a particular transaction, in return for payment of the net proceeds to us. There is no arrangement for funds to be received in an escrow, trust or similar arrangement. Sales of our Common Stock as contemplated in this prospectus supplement will be settled through the facilities of The Depository Trust Company or by such other means as we and the Sales Agents may agree.

We or the Sales Agents may suspend the offering upon notice and subject to other conditions. The offering of our Common Stock pursuant to the Sales Agreement will terminate upon the earlier of (i) the sale of all of the shares of our Common Stock subject to the Sales Agreement and (ii) the termination of the Sales Agreement by us or the Sales Agents as provided therein. This prospectus supplement and the accompanying prospectus may be made available in electronic format on a website maintained by the Sales Agents, and the Sales Agents may distribute this prospectus supplement and the accompanying prospectus electronically.

The Sales Agents will use commercially reasonable efforts, consistent with their sales and trading practices, to sell on our behalf all of the shares of our Common Stock requested to be sold by us under the terms and subject to the conditions set forth in the Sales Agreement. In connection with the sale of the shares of Common Stock on our behalf, each of the Sales Agents will be deemed to be an "underwriter" within the meaning of the Securities Act, and the compensation paid to each of the Sales Agents will be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to the Sales Agents against certain liabilities, including civil liabilities under the Securities Act.

We may engage in investment banking, brokerage and other dealings with the Sales Agents and their affiliates in the ordinary course of business and we expect that the Sales Agents and their affiliates will receive customary fees and commissions for their services in connection with these transactions.

Other Activities and Relationships

The Sales Agents and their respective affiliates are full service financial institutions engaged in various activities, which may include sales and trading, commercial and investment banking, advisory, investment management, investment research, principal investment, hedging, market making, brokerage and other financial and non-financial activities and services. The Sales Agents and certain of their respective affiliates have, from time to time, provided, and may in the future provide, a variety of these services to us and to persons and entities with relationships with us, for which they received or will receive customary fees and expenses.

In the ordinary course of their various business activities, the Sales Agents and their respective affiliates, officers, directors and employees may purchase, sell or hold a broad array of investments and actively trade securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments for their own accounts and for the accounts of their customers, and such investment and trading activities may involve or relate to our assets, securities and/or instruments (directly, as collateral securing other obligations or otherwise) and/or persons and entities with relationships with us. The Sales Agents and their respective affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such assets, securities or instruments and may at any time hold, or recommend to clients that they should acquire, long and/or short positions in such assets, securities and instruments.

Listing

Our Common Stock is listed on NYSE under the symbol "BKKT".

Transfer Agent and Registrar

The transfer agent and registrar for our Common Stock is Equiniti Trust Company. Its mailing address is 28 Liberty Street, 53rd Floor, New York, NY 10005 and its telephone number is (800) 937-5449.

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Selling Restrictions

Other than in the United States, no action has been taken by us or the Sales Agents that would permit a public offering of the shares of Common Stock offered by this prospectus supplement and the accompanying prospectus in any jurisdiction where action for that purpose is required. The shares of Common Stock offered by this prospectus supplement may not be offered or sold, directly or indirectly, nor may this prospectus supplement or any other offering material or advertisements in connection with the offer and sale of any such shares be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. Persons into whose possession this prospectus supplement comes are advised to inform themselves about and to observe any restrictions relating to the offering and the distribution of this prospectus supplement. This prospectus supplement does not constitute an offer to sell or a solicitation of an offer to buy any shares of Common Stock offered by this prospectus supplement in any jurisdiction in which such an offer or a solicitation is unlawful.

You should be aware that the laws and practices of certain countries require investors to pay stamp taxes and other charges in connection with purchases of securities.

Notice to Prospective Investors in the European Economic Area

In relation to each Member State of the European Economic Area (each, a "Relevant State"), no shares of Common Stock have been offered or will be offered pursuant to the offering to the public in that Relevant State prior to the publication of a prospectus in relation to the offering which has been approved by the competent authority in that Relevant State or, where appropriate, approved in another Relevant State and notified to the competent authority in that Relevant State, all in accordance with the Prospectus Regulation, except that shares of Common Stock may be offered to the public in that Relevant State at any time:

provided that no such offer of securities shall require us or the Sales Agents to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation.

In the case of any shares being offered to a financial intermediary as that term is used in Article 1(4) of the EU Prospectus Regulation, each financial intermediary will also be deemed to have represented, warranted and agreed that the shares acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any shares to the public, other than their offer or resale in a Relevant Member State to qualified investors as so defined or in circumstances in which the prior consent of the applicable Sales Agent(s) has been obtained to each such proposed offer or resale.

We, the Sales Agents and their affiliates will rely upon the truth and accuracy of the foregoing representations, warranties and agreements. Notwithstanding the above, a person who is not a "qualified investor" and who has notified the applicable Sales Agent(s) of such fact in writing may, with the prior consent of the applicable Sales Agent(s), be permitted to acquire shares in the offer.

For the purposes of this provision, the expression an "offer to the public" in relation to any securities in any Relevant State means the communication in any form and by any means of sufficient information on the terms of the offer and any securities to be offered so as to enable an investor to decide to purchase or subscribe for any securities, and the expression "Prospectus Regulation" means Regulation (EU) 2017/1129, as amended.

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United Kingdom

No shares of Common Stock have been offered or will be offered pursuant to the offering to the public in the United Kingdom prior to the publication of a prospectus in relation to the shares of Common Stock which has been approved by the Financial Conduct Authority, except that the shares of Common Stock may be offered to the public in the United Kingdom at any time:

provided that no such offer of the securities shall require us or the Sales Agents to publish a prospectus pursuant to Section 85 of the FSMA or supplement a prospectus pursuant to Article 23 of the UK Prospectus Regulation.

In the case of any shares being offered to a financial intermediary as that term is used in Article 1(4) of the UK Prospectus Regulation, each financial intermediary will also be deemed to have represented, warranted and agreed that the shares acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any shares to the public, other than their offer or resale in the United Kingdom to qualified investors as so defined or in circumstances in which the prior consent of the applicable Sales Agent(s) has been obtained to each such proposed offer or resale.

We, the Sales Agents and their affiliates will rely upon the truth and accuracy of the foregoing representations, warranties and agreements. Notwithstanding the above, a person who is not a "qualified investor" and who has notified the applicable Sales Agent(s) of such fact in writing may, with the prior consent of the applicable Sales Agent(s), be permitted to acquire shares in the offer.

For the purposes of this provision, the expression an "offer to the public" in relation to the securities in the United Kingdom means the communication in any form and by any means of sufficient information on the terms of the offer and any securities to be offered so as to enable an investor to decide to purchase or subscribe for any securities and the expression "UK Prospectus Regulation" means Regulation (EU) 2017/1129 as it forms part of domestic law by virtue of the European Union (Withdrawal) Act 2018.

Canada

The shares of Common Stock may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the shares of Common Stock must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser's province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser's province or territory for particulars of these rights or consult with a legal advisor.

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Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the Sales Agents are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

Israel

This document does not constitute a prospectus under the Israeli Securities Law, 5728-1968, or the Securities Law, and has not been filed with or approved by the Israel Securities Authority. In Israel, this prospectus is being distributed only to, and is directed only at, and any offer of the shares is directed only at, (i) a limited number of persons in accordance with the Israeli Securities Law and (ii) investors listed in the first addendum, or the Addendum, to the Israeli Securities Law, consisting primarily of joint investment in trust funds, provident funds, insurance companies, banks, portfolio managers, investment advisors, members of the Tel Aviv Stock Exchange, underwriters, venture capital funds, entities with equity in excess of NIS 50 million and "qualified individuals," each as defined in the Addendum (as it may be amended from time to time), collectively referred to as qualified investors (in each case, purchasing for their own account or, where permitted under the Addendum, for the accounts of their clients who are investors listed in the Addendum). Qualified investors are required to submit written confirmation that they fall within the scope of the Addendum, are aware of the meaning of same and agree to it.

Hong Kong

The shares may not be offered or sold in Hong Kong by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32 of the Laws of Hong Kong), or the Companies (Winding Up and Miscellaneous Provisions) Ordinance, or which do not constitute an invitation to the public within the meaning of the Securities and Futures Ordinance (Cap. 571 of the Laws of Hong Kong), or the Securities and Futures Ordinance, or (ii) to "professional investors" as defined in the Securities and Futures Ordinance and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a "prospectus" as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance, and no advertisement, invitation or document relating to the shares may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" in Hong Kong as defined in the Securities and Futures Ordinance and any rules made thereunder.

Singapore

This prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares may not be circulated or distributed, nor may the shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor (as defined under Section 4A of the Securities and Futures Act, Chapter 289 of Singapore, or the SFA) under Section 274 of the SFA, (ii) to a relevant person (as defined in Section 275(2) of the SFA) pursuant to Section 275(1) of the SFA, or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA, in each case subject to conditions set forth in the SFA.

Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of

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whom is an accredited investor, the securities (as defined in Section 239(1) of the SFA) of that corporation shall not be transferable for 6 months after that corporation has acquired the shares under Section 275 of the SFA except: (1) to an institutional investor under Section 274 of the SFA or to a relevant person (as defined in Section 275(2) of the SFA), (2) where such transfer arises from an offer in that corporation's securities pursuant to Section 275(1A) of the SFA, (3) where no consideration is or will be given for the transfer, (4) where the transfer is by operation of law, (5) as specified in Section 276(7) of the SFA, or (6) as specified in Regulation 32 of the Securities and Futures (Offers of Investments) (Shares and Debentures) Regulations 2005 of Singapore, or Regulation 32.

Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is a trust (where the trustee is not an accredited investor (as defined in Section 4A of the SFA)) whose sole purpose is to hold investments and each beneficiary of the trust is an accredited investor, the beneficiaries' rights and interest (howsoever described) in that trust shall not be transferable for 6 months after that trust has acquired the shares under Section 275 of the SFA except: (1) to an institutional investor under Section 274 of the SFA or to a relevant person (as defined in Section 275(2) of the SFA), (2) where such transfer arises from an offer that is made on terms that such rights or interest are acquired at a consideration of not less than S$200,000 (or its equivalent in a foreign currency) for each transaction (whether such amount is to be paid for in cash or by exchange of securities or other assets), (3) where no consideration is or will be given for the transfer, (4) where the transfer is by operation of law, (5) as specified in Section 276(7) of the SFA, or (6) as specified in Regulation 32.

Dubai

This prospectus supplement relates to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority (the "DFSA"). This prospectus supplement is intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. It must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement nor taken steps to verify the information set forth herein and has no responsibility for this prospectus supplement. The shares to which this prospectus supplement relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the shares offered should conduct their own due diligence on the shares. If you do not understand the contents of this prospectus supplement you should consult an authorized financial advisor.

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LEGAL MATTERS

The validity of the shares of our Common Stock offered by this prospectus supplement will be passed upon for us by Sullivan & Cromwell LLP, New York, New York. Certain legal matters in connection with this offering will be passed upon for the Sales Agents by Reed Smith LLP, New York, New York.

EXPERTS

The consolidated financial statements of Bakkt Holdings, Inc. as of and for the year ended December 31, 2024 appearing in the Company's Annual Report (Form 10-K), as supplemented by the Company's Current Report on Form 8-K filed with the Securities and Exchange Commission on December 10, 2025, have been incorporated by reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, included thereon, and incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The consolidated financial statements of Bakkt Holdings, Inc., at December 31, 2023 and for each of the two years in the period ended December 31, 2023 appearing in the Company's Annual Report (Form 10-K) for the period ended December 31, 2024, as supplemented by the Company's Current Report on Form 8-K filed with the Securities and Exchange Commission on December 10, 2025, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such financial statements are, and audited financial statements to be included in subsequently filed documents will be, incorporated herein in reliance upon such reports pertaining to such financial statements (to the extent covered by consents filed with the Securities and Exchange Commission) given on the authority of such firm as experts in accounting and auditing.

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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The documents listed below are incorporated by reference into this prospectus:

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus is modified or superseded for purposes of the prospectus to the extent that a statement contained in this prospectus or in any other subsequently filed document that also is or is deemed to be incorporated by reference herein modifies or supersedes such statement.

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 this prospectus but not delivered with the prospectus.

We are an Exchange Act reporting company and are required to file periodic reports on Form 10-K and 10-Q and Current Reports on Form 8-K. The SEC maintains an internet website that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC, including Bakkt Holdings, Inc. at www.sec.gov/EDGAR. You may also access our reports and proxy statements free of charge at our website, www.bakkt.com, which website is not incorporated into this prospectus supplement.

You may obtain a copy of any of our filings, at no cost, by contacting us at:

One Liberty Plaza,

One Liberty Street, Suite 305-306

New York, New York 10006

(678) 534-5849

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PROSPECTUS

Bakkt Holdings, Inc.

$1,000,000,000

Class A Common Stock

Preferred Stock

Debt Securities

Warrants

Units

We may issue securities from time to time in one or more offerings, in amounts, at prices and on terms determined at the time of offering. This prospectus describes the general terms of these securities and the general manner in which these securities will be offered. We will provide the specific terms of these securities in supplements to this prospectus, which will also describe the specific manner in which these securities will be offered and may also supplement, update or amend information contained in this prospectus. You should read this prospectus and any applicable prospectus supplement before you invest. The aggregate offering price of the securities we sell pursuant to this prospectus will not exceed $1,000,000,000.

The securities may be sold directly to you, through agents or through underwriters and dealers. If agents, underwriters or dealers are used to sell the securities, we will name them and describe their compensation in a prospectus supplement. The price to the public of those securities and the net proceeds we expect to receive from that sale will also be set forth in a prospectus supplement.

Our Class A common stock, par value $0.0001 per share ("Class A Common Stock"), and our public warrants to purchase Class A Common Stock are listed on the New York Stock Exchange ("NYSE") under the symbols "BKKT" and "BKKT WS," respectively. Each prospectus supplement will indicate whether the securities offered thereby will be listed on any securities exchange.

Investing in these securities involves risks. Please carefully read the information under the headings "Risk Factors" beginning on page 6 of this prospectus and "Item 1A - Risk Factors" of our most recent Annual Report on Form 10-K and any Quarterly Report on Form 10-Q filed subsequently to such Form 10-K that is incorporated by reference in this prospectus before you invest in our securities. In addition, please carefully read the information under the heading "Risk Factors Related to the Update of Our Investment Policy" in Exhibit 99.1 to our Current Report on Form 8-K filed on June 10, 2025 that is incorporated by reference in this prospectus before you invest in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is July 3, 2025.

TABLE OF CONTENTS

i

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission (the "SEC") using a "shelf" registration process. Under this shelf registration process, we may from time to time sell any combination of the securities described in this prospectus in one or more offerings.

This prospectus provides you with a general description of the securities that may be offered. Each time we sell securities, we will provide one or more prospectus supplements that will contain specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any applicable prospectus supplement together with the additional information described under the heading "Where You Can Find More Information."

We have not authorized anyone to provide you with information that is different from that contained, or incorporated by reference, in this prospectus, any applicable prospectus supplement or in any related free writing prospectus. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus and any applicable prospectus supplement or any related free writing prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in the applicable prospectus supplement or an offer to sell or the solicitation of an offer to buy such securities in any circumstances in which such offer or solicitation is unlawful. You should assume that the information appearing in this prospectus, any prospectus supplement, the documents incorporated by reference and any related free writing prospectus is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since those dates.

ii

1

2

3

4

5

RISK FACTORS

An investment in our securities involves a high degree of risk. The prospectus supplement applicable to each offering of our securities will contain a discussion of the risks applicable to an investment in our securities. Prior to making a decision about investing in our securities, you should carefully consider the specific factors discussed under the section in the applicable prospectus supplement captioned "Risk Factors," together with all of the other information contained or incorporated by reference in the prospectus supplement or appearing or incorporated by reference in this prospectus. You should also consider the risks, uncertainties and assumptions discussed under "Part I-Item 1A-Risk Factors" of our most recent Annual Report on Form 10-K and in "Part II-Item 1A-Risk Factors" of our Quarterly Reports on Form 10-Q filed subsequently to such Form 10-K that are incorporated herein by reference, as may be amended, supplemented or superseded from time to time by other reports we file with the SEC in the future. In addition, you should consider the risks, uncertainties and assumptions discussed under the heading "Risk Factors Related to the Update of Our Investment Policy" in Exhibit 99.1 to our Current Report on Form 8-K filed on June 10, 2025 that is incorporated by reference in this prospectus before you invest in our securities. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations.

6

FORWARD-LOOKING STATEMENTS

This prospectus, any accompanying prospectus supplement and the documents incorporated by reference herein and therein contain forward-looking statements within the meaning of the federal securities laws, which statements involve substantial risks and uncertainties. Forward-looking statements generally relate to future events or our future financial or operating performance. You can identify forward-looking statements because they contain words such as "anticipate," "believe," "continue," "could," "estimate," "expect," "intends," "may," "might," "plan," "possible," "potential," "predict," "project," "should," "will," "would," the negative of such terms, and other similar expressions that are intended to identify forward-looking statements. These forward-looking statements are based on management's current expectations, assumptions, hopes, beliefs, intentions and strategies regarding future events and are based on currently available information as to the outcome and timing of future events. We caution you that these forward-looking statements are subject to all of the risks and uncertainties, most of which are difficult to predict and many of which are beyond our control, incident to our business. Forward-looking statements included or incorporated by reference into this prospectus may include, for example, statements about:

These forward-looking statements are based on information available as of the date they were made and reflect management's expectations, forecasts and assumptions as of such date, and involve a number of judgments, known and/or unknown risks and uncertainties. Accordingly, forward-looking statements should not be relied upon as representing our views as of any subsequent date. We do not undertake any obligation to update any forward-looking statement to reflect events or circumstances after the date they were made, whether as a result of new information, future events or otherwise, except as may be required under applicable law.

You should not place undue reliance on these forward-looking statements. Should one or more of a number of known and unknown risks and uncertainties materialize, or should any of our assumptions prove incorrect, our actual results or performance may be materially different from those expressed or implied by these forward-looking statements. Some factors that could cause actual results to differ include, but are not limited to:

7

8

9

USE OF PROCEEDS

We will retain broad discretion over the use of the net proceeds to us from the sale of our securities under this prospectus. Unless otherwise provided in the applicable prospectus supplement, we currently expect to use the net proceeds that we receive from this offering for working capital and other general corporate purposes.

DESCRIPTION OF CAPITAL STOCK

The description of our capital stock is incorporated by reference to Exhibit 4.9 to our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, filed with the SEC on March 20, 2025.

10

DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplement, summarizes certain general terms and provisions of the debt securities that we may offer under this prospectus. When we offer to sell a particular series of debt securities, we will describe the specific terms of the series in a supplement to this prospectus. We will also indicate in the supplement to what extent the general terms and provisions described in this prospectus apply to a particular series of debt securities.

We may issue debt securities either separately, or together with, or upon the conversion or exercise of or in exchange for, other securities described in this prospectus. Debt securities may be our senior, senior subordinated or subordinated obligations and, unless otherwise specified in a supplement to this prospectus, the debt securities will be our direct, unsecured obligations and may be issued in one or more series.

The debt securities will be issued under an indenture between us and a trustee to be identified in an accompanying prospectus supplement. We have summarized select portions of the indenture below. The summary is not complete. The form of the indenture has been filed as an exhibit to the registration statement of which this prospectus forms a part and you should read the indenture for provisions that may be important to you. In the summary below, we have included references to the section numbers of the indenture so that you can easily locate these provisions. Capitalized terms used in the summary and not defined herein have the meanings specified in the indenture.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of our board of directors and set forth or determined in the manner provided in a resolution of our board of directors, in an officer's certificate or by a supplemental indenture. The particular terms of each series of debt securities will be described in a prospectus supplement relating to such series (including any pricing supplement or term sheet).

We can issue an unlimited amount of debt securities under the indenture that may be in one or more series with the same or various maturities, at par, at a premium, or at a discount. We will set forth in a prospectus supplement (including any pricing supplement or term sheet) relating to any series of debt securities being offered the aggregate principal amount and the following terms of the debt securities, if applicable:

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We may issue debt securities that provide for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturity pursuant to the terms of the indenture. We will provide you with information on the federal income tax considerations and other special considerations applicable to any of these debt securities in the applicable prospectus supplement.

If we denominate the purchase price of any of the debt securities in a foreign currency or currencies or a foreign currency unit or units, or if the principal of and any premium and interest on any series of debt securities

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is payable in a foreign currency or currencies or a foreign currency unit or units, we will provide you with information on the restrictions, elections, general tax considerations, specific terms and other information with respect to that issue of debt securities and such foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

Transfer and Exchange

Each debt security will be represented by either one or more global securities registered in the name of a clearing agency registered under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), which we refer to as the depositary, or a nominee of the depositary (we will refer to any debt security represented by a global debt security as a "book-entry debt security"), or a certificate issued in definitive registered form (we will refer to any debt security represented by a certificated security as a "certificated debt security") as set forth in the applicable prospectus supplement. Except as set forth under the heading "Global Debt Securities and Book-Entry System" below, book-entry debt securities will not be issuable in certificated form.

Certificated Debt Securities

You may transfer or exchange certificated debt securities at any office we maintain for this purpose in accordance with the terms of the indenture. No service charge will be made for any transfer or exchange of certificated debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with a transfer or exchange.

You may effect the transfer of certificated debt securities and the right to receive the principal of, premium and interest on certificated debt securities only by surrendering the certificate representing those certificated debt securities and either reissuance by us or the trustee of the certificate to the new holder or the issuance by us or the trustee of a new certificate to the new holder.

Global Debt Securities and Book-Entry System

Each global debt security representing book-entry debt securities will be deposited with, or on behalf of, the depositary, and registered in the name of the depositary or a nominee of the depositary.

Covenants

We will set forth in the applicable prospectus supplement any restrictive covenants applicable to any issue of debt securities.

No Protection in the Event of a Change of Control

Unless we state otherwise in the applicable prospectus supplement, the debt securities will not contain any provisions which may afford holders of the debt securities protection in the event we have a change in control or in the event of a highly leveraged transaction (whether or not such transaction results in a change in control) which could adversely affect holders of debt securities.

Consolidation, Merger and Sale of Assets

We may not consolidate with or merge with or into, or convey, transfer or lease all or substantially all of our properties and assets to any person, which we refer to as a successor person, unless:

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Notwithstanding the above, any of our subsidiaries may consolidate with, merge into or transfer all or part of its properties to us.

Events of Default

"Event of Default" means with respect to any series of debt securities, any of the following:

No Event of Default with respect to a particular series of debt securities (except as to certain events of bankruptcy, insolvency or reorganization) necessarily constitutes an Event of Default with respect to any other series of debt securities. The occurrence of certain Events of Default or an acceleration under the indenture may constitute an event of default under certain indebtedness of ours or our subsidiaries outstanding from time to time.

We will provide the trustee written notice of any Default or Event of Default within 30 days of becoming aware of the occurrence of such Default or Event of Default, which notice will describe in reasonable detail the status of such Default or Event of Default and what action we are taking or propose to take in respect thereof.

If an Event of Default with respect to debt securities of any series at the time outstanding occurs and is continuing, then the trustee or the holders of not less than 25% in principal amount of the outstanding debt securities of that series may, by a notice in writing to us (and to the trustee if given by the holders), declare to be due and payable immediately the principal of (or, if the debt securities of that series are discount securities, that portion of the principal amount as may be specified in the terms of that series) and accrued and unpaid interest, if any, on all debt securities of that series. In the case of an Event of Default resulting from certain events of bankruptcy, insolvency or reorganization, the principal (or such specified amount) of and accrued and unpaid interest, if any, on all outstanding debt securities will become and be immediately due and payable without any declaration or other act on the part of the trustee or any holder of outstanding debt securities. At any time after a declaration of acceleration with respect to debt securities of any series has been made, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of a majority in principal amount of the outstanding debt securities of that series may rescind and annul the acceleration if all Events of Default, other than the non-payment of accelerated principal and interest, if any, with respect to debt securities of that series, have been cured or waived as provided in the indenture. We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of such discount securities upon the occurrence of an Event of Default.

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The indenture provides that the trustee may refuse to perform any duty or exercise any of its rights or powers under the indenture unless the trustee receives indemnity satisfactory to it against any cost, liability or expense which might be incurred by it in performing such duty or exercising such right or power. Subject to certain rights of the trustee, the holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to the debt securities of that series.

No holder of any debt security of any series will have any right to institute any proceeding, judicial or otherwise, with respect to the indenture or for the appointment of a receiver or trustee, or for any remedy under the indenture, unless:

Notwithstanding any other provision in the indenture, the holder of any debt security will have an absolute and unconditional right to receive payment of the principal of, premium and any interest on that debt security on or after the due dates expressed in that debt security and to institute suit for the enforcement of payment.

The indenture requires us, within 120 days after the end of our fiscal year, to furnish to the trustee a statement as to compliance with the indenture. If a Default or Event of Default occurs and is continuing with respect to the securities of any series and if it is known to a responsible officer of the trustee, the trustee shall send to each securityholder of the securities of that series notice of a Default or Event of Default within 90 days after it occurs or, if later, after a responsible officer of the trustee has knowledge of such Default or Event of Default. The indenture provides that the trustee may withhold notice to the holders of debt securities of any series of any Default or Event of Default (except in payment on any debt securities of that series) with respect to debt securities of that series if the trustee determines in good faith that withholding notice is in the interest of the holders of those debt securities.

Modification and Waiver

We and the trustee may modify, amend or supplement the indenture or the debt securities of any series without the consent of any holder of any debt security:

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We may also modify and amend the indenture with the consent of the holders of at least a majority in principal amount of the outstanding debt securities of each series affected by the modifications or amendments. We may not make any modification or amendment without the consent of the holders of each affected debt security then outstanding if that amendment will:

Except for certain specified provisions, the holders of at least a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all debt securities of that series waive our compliance with provisions of the indenture. The holders of a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all the debt securities of such series waive any past default under the indenture with respect to that series and its consequences, except a default in the payment of the principal of, premium or any interest on any debt security of that series; provided, however, that the holders of a majority in principal amount of the outstanding debt securities of any series may rescind an acceleration and its consequences, including any related payment default that resulted from the acceleration.

Defeasance of Debt Securities and Certain Covenants in Certain Circumstances

Legal Defeasance

The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, we may be discharged from any and all obligations in respect of the debt securities of any series (subject to certain exceptions). We will be so discharged upon the irrevocable deposit with the trustee, in trust, of money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. dollars, government obligations of the government that issued or caused to be issued such

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currency, that, through the payment of interest and principal in accordance with their terms, will provide money or U.S. government obligations in an amount sufficient in the opinion of a nationally recognized firm of independent public accountants or investment bank to pay and discharge each installment of principal, premium and interest on and any mandatory sinking fund payments in respect of the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities.

This discharge may occur only if, among other things, we have delivered to the trustee an opinion of counsel stating that we have received from, or there has been published by, the United States Internal Revenue Service a ruling or, since the date of execution of the indenture, there has been a change in the applicable United States federal income tax law, in either case to the effect that, and based thereon such opinion shall confirm that, the holders of the debt securities of that series will not recognize income, gain or loss for United States federal income tax purposes as a result of the deposit, defeasance and discharge and will be subject to United States federal income tax on the same amounts and in the same manner and at the same times as would have been the case if the deposit, defeasance and discharge had not occurred.

Defeasance of Certain Covenants

The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, upon compliance with certain conditions:

We refer to this as covenant defeasance. The conditions include:

No Personal Liability of Directors, Officers, Employees or Stockholders

None of our past, present or future directors, officers, employees or stockholders, as such, will have any liability for any of our obligations under the debt securities or the indenture or for any claim based on, or in

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respect or by reason of, such obligations or their creation. By accepting a debt security, each holder waives and releases all such liability. This waiver and release is part of the consideration for the issue of the debt securities. However, this waiver and release may not be effective to waive liabilities under U.S. federal securities laws, and it is the view of the SEC that such a waiver is against public policy.

Governing Law

The indenture and the debt securities, including any claim or controversy arising out of or relating to the indenture or the securities, will be governed by the laws of the State of New York.

The indenture will provide that we, the trustee and the holders of the debt securities (by their acceptance of the debt securities) irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to the indenture, the debt securities or the transactions contemplated thereby.

The indenture will provide that any legal suit, action or proceeding arising out of or based upon the indenture or the transactions contemplated thereby may be instituted in the federal courts of the United States of America located in the City of New York or the courts of the State of New York in each case located in the City of New York, and we, the trustee and the holder of the debt securities (by their acceptance of the debt securities) irrevocably submit to the non-exclusive jurisdiction of such courts in any such suit, action or proceeding. The indenture will further provide that service of any process, summons, notice or document by mail (to the extent allowed under any applicable statute or rule of court) to such party's address set forth in the indenture will be effective service of process for any suit, action or other proceeding brought in any such court. The indenture will further provide that we, the trustee and the holders of the debt securities (by their acceptance of the debt securities) irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the courts specified above and irrevocably and unconditionally waive and agree not to plead or claim any such suit, action or other proceeding has been brought in an inconvenient forum.

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DESCRIPTION OF WARRANTS

We may issue warrants to purchase debt securities, preferred stock or Class A Common Stock. We may offer warrants separately or together with one or more additional warrants, debt securities, preferred stock or Class A Common Stock, or any combination of those securities in the form of units, as described in the applicable prospectus supplement. If we issue warrants as part of a unit, the applicable prospectus supplement will specify whether those warrants may be separated from the other securities in the unit prior to the expiration date of the warrants. The applicable prospectus supplement will also describe the following terms of any warrants:

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DESCRIPTION OF UNITS

We may issue units comprising two or more securities described in this prospectus in any combination. For example, we might issue units consisting of a combination of debt securities and warrants to purchase Class A Common Stock. The following description sets forth certain general terms and provisions of the units that we may offer pursuant to this prospectus. The particular terms of the units and the extent, if any, to which the general terms and provisions may apply to the units so offered will be described in the applicable prospectus supplement.

Each unit will be issued so that the holder of the unit also is the holder of each security included in the unit. Thus, the unit will have the rights and obligations of a holder of each included security. Units will be issued pursuant to the terms of a unit agreement, which 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. A copy of the forms of the unit agreement and the unit certificate relating to any particular issue of units will be filed with the SEC each time we issue units, and you should read those documents for provisions that may be important to you. For more information on how you can obtain copies of the forms of the unit agreement and the related unit certificate, see the section of this prospectus titled "Where You Can Find More Information."

The prospectus supplement relating to any particular issuance of units will describe the terms of those units, including, to the extent applicable, the following:

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PLAN OF DISTRIBUTION

We may sell securities:

In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing securityholders.

We may directly solicit offers to purchase securities or agents may be designated to solicit such offers. We will, in the prospectus supplement relating to such offering, name any agent that could be viewed as an underwriter under the Securities Act of 1933, as amended (the "Securities Act"), and describe any commissions that we must pay. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

The distribution of the securities may be effected from time to time in one or more transactions:

Each prospectus supplement will describe the method of distribution of the securities and any applicable restrictions.

The prospectus supplement with respect to the securities of a particular series will describe the terms of the offering of the securities, including the following:

If any underwriters or agents are utilized in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.

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If a dealer is utilized in the sale of the securities in respect of which the prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.

Agents, underwriters, dealers and other persons may be entitled under agreements that they may enter into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act.

If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:

The underwriters and other persons acting as agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.

Certain agents, underwriters and dealers, and their associates and affiliates may be customers of, have borrowing relationships with, engage in other transactions with, and/or perform services, including investment banking services, for us or one or more of our respective affiliates in the ordinary course of business.

In order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may over-allot in connection with the offering, creating a short position for their own accounts. In addition, to cover over-allotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

Under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in one business day, unless the parties to any such trade expressly agree otherwise. The applicable prospectus supplement may provide that the original issue date for your securities may be more than one scheduled business day after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities before the original issue date for your securities, you may be required to make alternative settlement arrangements to prevent a failed settlement.

The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.

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VALIDITY OF THE SECURITIES

The validity of the securities offered hereby will be passed upon for us by Sullivan & Cromwell LLP, New York, New York. Additional legal matters may be passed on for us, or any underwriters, dealers or agents by counsel we will name in the applicable prospectus supplement.

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EXPERTS

The consolidated financial statements of Bakkt Holdings, Inc. as of and for the year ended December 31, 2024 appearing in the Company's Annual Report (Form 10-K) have been incorporated by reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, included thereon, and incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The consolidated financial statements of Bakkt Holdings, Inc., at December 31, 2023 and for each of the two years in the period ended December 31, 2023 appearing in the Company's Annual Report (Form 10-K) for the period ended December 31, 2024 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such financial statements are, and audited financial statements to be included in subsequently filed documents will be, incorporated herein in reliance upon such reports pertaining to such financial statements (to the extent covered by consents filed with the Securities and Exchange Commission) given on the authority of such firm as experts in accounting and auditing.

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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 SEC filings are available to the public over the Internet at the SEC's website at www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at investors.bakkt.com. Information accessible on or through our website is not a part of this prospectus.

This prospectus and any prospectus supplement is part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. You should review the information and exhibits in the registration statement for further information on us and our consolidated subsidiaries and the securities that we are offering. Forms of any indenture or other documents establishing the terms of the offered securities are filed as exhibits to the registration statement of which this prospectus forms a part or under cover of a Current Report on Form 8-K and incorporated in this prospectus by reference. Statements in this prospectus or any prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should read the actual documents for a more complete description of the relevant matters.

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INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference much of the information that we file with the SEC, 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 in this prospectus is considered to be part of this prospectus. Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated by reference in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (in each case, other than those documents or the portions of those documents furnished pursuant to Items 2.02 or 7.01 of any Current Report on Form 8-K and, except as may be noted in any such Form 8-K, exhibits filed on such form that are related to such information), until the offering of the securities under the registration statement of which this prospectus forms a part is terminated or completed:

You may request a copy of these filings, at no cost, by writing or telephoning us at the following address:

10000 Avalon Boulevard, Suite 1000

Alpharetta, Georgia 30009

(678) 534-5849

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus or any accompanying prospectus supplement.

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Bakkt Holdings, Inc.

(to be renamed Bakkt, Inc.)

Up to $300,000,000

Class A Common Stock

PROSPECTUS SUPPLEMENT

January 20, 2026