Primary Offering Prospectus (Form 424B2)

Fixed to Floating Rate Notes due 2035

Based Inversely on the 10-Year Constant Maturity Treasury Rate

Fully and Unconditionally Guaranteed by Morgan Stanley

As further described below, interest will accrue and be payable on the notes quarterly, in arrears, (i) from the original issue date toOctober 31, 2026: at a rate of 8.50% per annum and (ii) fromOctober 31, 2026tomaturity: at a variable rate per annum equal to the difference between 8.50% and the 10-Year Constant Maturity Treasury Rate, subject to the minimum interest rate of 0.00% per annum.

During the floating interest rate period, the interest rate is inversely linked to the reference rate and will be close or equal to zero if the reference rate approaches or reaches 8.50%.

All payments are subject to our credit risk. If we default on our obligations, you could lose some or all of your investment. These notes are not secured obligations and you will not have any security interest in, or otherwise have any access to, any underlying reference asset or assets.

(1)Morgan Stanley or one of our affiliates will pay varying discounts and commissions to dealers, including Morgan Stanley Wealth Management (an affiliate of the agent) and their financial advisors, of up to $ per note depending on market conditions. See “Supplemental Information Concerning Plan of Distribution; Conflicts of Interest.” For additional information, see “Plan of Distribution (Conflicts of Interest)” in the accompanying prospectus supplement.

(2)See “Use of Proceeds and Hedging” on page 9.

The notes involve risks not associated with an investment in ordinary debt securities. See “Risk Factors” beginning on page 6.

The Securities and Exchange Commission and state securities regulators have not approved or disapproved these notes, or determined if this pricing supplement or the accompanying prospectus supplement and prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

You should read this document together with the related prospectus supplement and prospectus, each of which can be accessed via the hyperlinks below, before you decide to invest. When you read the accompanying prospectus supplement, please note that all references in such supplement to the prospectus dated November 16, 2023, or to any sections therein, should refer instead to the accompanying prospectus dated April 12, 2024 or to the corresponding sections of such prospectus, as applicable.

Prospectus Supplement dated November 16, 2023 Prospectus dated April 12, 2024

References to “we,” “us” and “our” refer to Morgan Stanley or MSFL, or Morgan Stanley and MSFL collectively, as the context requires.

The notes are not deposits or savings accounts and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency or instrumentality, nor are they obligations of, or guaranteed by, a bank.

Fixed to Floating Rate Notes due 2035

Based on the 10-Year Constant Maturity Treasury Rate

Terms continued from previous page:

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The Notes

The notes offered are debt securities of Morgan Stanley Finance LLC (“MSFL”) and are fully and unconditionally guaranteed by Morgan Stanley. From the original issue date until October 31, 2026, interest on the notes will accrue and be payable quarterly, in arrears, at 8.50% per annum, and thereafter, during the floating interest rate period, interest on the notes will accrue and be payable quarterly, in arrears, at a variable rate per annum equal to the difference between 8.50% and the reference rate, subject to the minimum interest rate of 0.00% per annum. During the floating interest rate period, the interest rate is inversely linked to the reference rate and will be close or equal to zero if the reference rate approaches or reaches 8.50%.

We describe the basic features of the notes in the sections of the accompanying prospectus called “Description of Debt Securities—Fixed Rate Debt Securities” and “—Floating Rate Debt Securities” and prospectus supplement called “Description of Notes,” subject to and as modified by the provisions described below.

All payments on the notes are subject to our credit risk.

The stated principal amount and issue price of each note is $1,000. This price includes costs associated with issuing, selling, structuring and hedging the notes, which are borne by you, and, consequently, the estimated value of the notes on the pricing date will be less than the issue price. We estimate that the value of each note on the pricing date will be approximately $939.00, or within $59.00 of that estimate. Our estimate of the value of the notes as determined on the pricing date will be set forth in the final pricing supplement.

What goes into the estimated value on the pricing date?

In valuing the notes on the pricing date, we take into account that the notes comprise both a debt component and a performance-based component linked to 10CMT. The estimated value of the notes is determined using our own pricing and valuation models, market inputs and assumptions relating to 10CMT, instruments based on 10CMT, volatility and other factors including current and expected interest rates, as well as an interest rate related to our secondary market credit spread, which is the implied interest rate at which our conventional fixed rate debt trades in the secondary market.

What determines the economic terms of the notes?

In determining the economic terms of the notes, including the interest rate and the minimum interest rate applicable to each interest payment period during the floating interest rate period, we use an internal funding rate, which is likely to be lower than our secondary market credit spreads and therefore advantageous to us. If the issuing, selling, structuring and hedging costs borne by you were lower or if the internal funding rate were higher, one or more of the economic terms of the notes would be more favorable to you.

What is the relationship between the estimated value on the pricing date and the secondary market price of the notes?

The price at which MS & Co. purchases the notes in the secondary market, absent changes in market conditions, including those related to interest rates and 10CMT, may vary from, and be lower than, the estimated value on the pricing date, because the secondary market price takes into account our secondary market credit spread as well as the bid-offer spread that MS & Co. would charge in a secondary market transaction of this type, the costs of unwinding the related hedging transactions and other factors.

MS & Co. may, but is not obligated to, make a market in the notes and, if it once chooses to make a market, may cease doing so at any time.

Additional Provisions

Reference Rate

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CMT rate, taking into account all available information that in good faith it considers relevant including, without limitation, an industry-accepted rate of interest in the over-the-counter derivatives market or for U.S. dollar-denominated floating rate notes (if any).”

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Historical Information

The following graph sets forth the historical percentage levels of the reference rate as published by the Board of Governors of the Federal Reserve System for the period from January 1, 2020 to October 3, 2025. The historical levels of the reference rate should not be taken as an indication of its future performance and no assurance can be given as to the level of the reference rate on any interest determination date. In addition, the following graph does not reflect the return the notes would have yielded during the period presented, in part because, during the floating interest rate period, the interest rate is inversely linked to the reference rate. We obtained the information in the graph below from Bloomberg Financial Markets (“H15T10Y Index”), without independent verification.

* The red line in the graph above represents the minimum interest rate of 0.00% per annum applicable to each interest payment period during the floating interest rate period. During the floating interest rate period, the interest rate is inversely linked to the reference rate and will be close or equal to zero if the reference rate approaches or reaches 8.50%.

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Risk Factors

The notes involve risks not associated with an investment in ordinary floating rate notes. An investment in the notes entails significant risks not associated with similar investments in a conventional debt security, including, but not limited to, fluctuations in the reference rate, and other events that are difficult to predict and beyond our control. This section describes the material risks relating to the notes. For a complete list of risk factors, please see the accompanying prospectus supplement and prospectus. You should carefully consider whether the notes are suited to your particular circumstances before you decide to purchase them. Accordingly, prospective investors should consult their financial and legal advisers as to the risks entailed by an investment in the notes and the suitability of the notes in light of their particular circumstances.

Risks Relating to an Investment in the Notes

￭During the floating interest rate period, the amount of interest payable on the notes is inversely related to the reference rate. With respect to each interest payment period during the floating interest rate period, any interest you may receive is based inversely on the level of the reference rate because the interest rate will be equal to the difference between 8.50% and the reference rate on the related interest determination date. If the reference rate increases as of any interest determination date, the difference between 8.50% and the reference rate will decrease and the interest you will earn, if any, with respect to the related interest payment period will decrease and could be zero.

￭The interest rate with respect to each interest payment period during the floating interest rate period will likely be less than 8.50%. With respect to each interest payment period during the floating interest rate period, interest will accrue on the notes at a variable rate per annum equal to the difference between 8.50% and the reference rate. Because it is unlikely that the reference rate will be as low as or lower than 0%, the interest rate with respect to each such interest payment period will likely be less than 8.50%.

￭The historical performance of the reference rate is not an indication of future performance. The historical performance of the reference rate should not be taken as an indication of future performance during the term of the notes. Changes in the level of the reference rate will affect the trading price of the notes, but it is impossible to predict whether such level will rise or fall. There can be no assurance that the reference rate will be positive.

￭Investors are subject to our credit risk, and any actual or anticipated changes to our credit ratings or credit spreads may adversely affect the market value of the notes. Investors are dependent on our ability to pay all amounts due on the notes on interest payment dates and at maturity and therefore investors are subject to our credit risk and to changes in the market’s view of our creditworthiness. If we default on our obligations under the notes, your investment would be at risk and you could lose some or all of your investment. As a result, the market value of the notes prior to maturity will be affected by changes in the market’s view of our creditworthiness. Any actual or anticipated decline in our credit ratings or increase in the credit spreads charged by the market for taking our credit risk is likely to adversely affect the value of the notes.

￭As a finance subsidiary, MSFL has no independent operations and will have no independent assets. As a finance subsidiary, MSFL has no independent operations beyond the issuance and administration of its securities and will have no independent assets available for distributions to holders of MSFL securities if they make claims in respect of such securities in a bankruptcy, resolution or similar proceeding. Accordingly, any recoveries by such holders will be limited to those available under the related guarantee by Morgan Stanley and that guarantee will rank pari passu with all other unsecured, unsubordinated obligations of Morgan Stanley. Holders will have recourse only to a single claim against Morgan Stanley and its assets under the guarantee. Holders of securities issued by MSFL should accordingly assume that in any such proceedings they would not have any priority over and should be treated pari passu with the claims of other unsecured, unsubordinated creditors of Morgan Stanley, including holders of Morgan Stanley-issued securities.

￭The price at which the notes may be sold prior to maturity will depend on a number of factors and may be substantially less than the amount for which they were originally purchased. Some of these factors include, but are not limited to: (i) actual or anticipated changes in the level of the reference rate, (ii) volatility of the level of the reference rate, (iii) changes in interest and yield rates, (iv) any actual or anticipated changes in our credit ratings or credit spreads and (v) time remaining to maturity. Generally, the longer the time remaining to maturity and the more tailored the exposure, the more the market price of the notes will be affected by the other factors described in the preceding sentence. This can lead to significant adverse changes in the market price of securities like the notes.

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Depending on the actual or anticipated level of the reference rate and interest and yield rates, the market value of the notes is expected to decrease and you may receive substantially less than 100% of the issue price if you are able to sell your notes prior to maturity.

￭The rate we are willing to pay for securities of this type, maturity and issuance size is likely to be lower than the rate implied by our secondary market credit spreads and advantageous to us. Both the lower rate and the inclusion of costs associated with issuing, selling, structuring and hedging the notes in the original issue price reduce the economic terms of the notes, cause the estimated value of the notes to be less than the original issue price and will adversely affect secondary market prices. Assuming no change in market conditions or any other relevant factors, the prices, if any, at which dealers, including MS & Co., are willing to purchase the notes in secondary market transactions will likely be significantly lower than the original issue price, because secondary market prices will exclude the issuing, selling, structuring and hedging-related costs that are included in the original issue price and borne by you and because the secondary market prices will reflect our secondary market credit spreads and the bid-offer spread that any dealer would charge in a secondary market transaction of this type, the costs of unwinding the related hedging transactions as well as other factors.

The inclusion of the costs of issuing, selling, structuring and hedging the notes in the original issue price and the lower rate we are willing to pay as issuer make the economic terms of the notes less favorable to you than they otherwise would be.

￭The estimated value of the notes is determined by reference to our pricing and valuation models, which may differ from those of other dealers and is not a maximum or minimum secondary market price. These pricing and valuation models are proprietary and rely in part on subjective views of certain market inputs and certain assumptions about future events, which may prove to be incorrect. As a result, because there is no market-standard way to value these types of securities, our models may yield a higher estimated value of the notes than those generated by others, including other dealers in the market, if they attempted to value the notes. In addition, the estimated value on the pricing date does not represent a minimum or maximum price at which dealers, including MS & Co., would be willing to purchase your notes in the secondary market (if any exists) at any time. The value of your notes at any time after the date of this pricing supplement will vary based on many factors that cannot be predicted with accuracy, including our creditworthiness and changes in market conditions.

￭The notes will not be listed on any securities exchange and secondary trading may be limited. The notes will not be listed on any securities exchange. Therefore, there may be little or no secondary market for the notes. MS & Co. may, but is not obligated to, make a market in the notes and, if it once chooses to make a market, may cease doing so at any time. When it does make a market, it will generally do so for transactions of routine secondary market size at prices based on its estimate of the current value of the notes, taking into account its bid/offer spread, our credit spreads, market volatility, the notional size of the proposed sale, the cost of unwinding any related hedging positions, the time remaining to maturity and the likelihood that it will be able to resell the notes. Even if there is a secondary market, it may not provide enough liquidity to allow you to trade or sell the notes easily. Since other broker-dealers may not participate significantly in the secondary market for the notes, the price at which you may be able to trade your notes is likely to depend on the price, if any, at which MS & Co. is willing to transact. If, at any time, MS & Co. were to cease making a market in the notes, it is likely that there would be no secondary market for the notes. Accordingly, you should be willing to hold your notes to maturity.

￭Morgan Stanley & Co. LLC, which is a subsidiary of Morgan Stanley and an affiliate of MSFL, has determined the estimated value on the pricing date. MS & Co. has determined the estimated value of the notes on the pricing date.

￭Our affiliates may publish research that could affect the market value of the notes. They also expect to hedge the issuer’s obligations under the notes. One or more of our affiliates may, at present or in the future, publish research reports with respect to movements in interest rates generally or the reference rate specifically. This research is modified from time to time without notice to you and may express opinions or provide recommendations that are inconsistent with purchasing or holding the notes. Any of these activities may affect the market value of the notes. In addition, our affiliates expect to hedge the issuer’s obligations under the notes and they may realize a profit from that expected hedging activity even if investors do not receive a favorable investment return under the terms of the notes or in any secondary market transaction.

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￭The calculation agent, which is a subsidiary of Morgan Stanley and an affiliate of MSFL, will make determinations with respect to the notes. Any of these determinations made by the calculation agent may adversely affect the payout to investors. Moreover, certain determinations made by the calculation agent may require it to exercise discretion and make subjective judgments, such as with respect to the reference rate. These potentially subjective determinations may adversely affect the payout to you on the notes. For further information regarding these types of determinations, see “Description of Debt Securities―Base Rates—CMT Rate Debt Securities” and related definitions in the accompanying prospectus, subject to and as modified by the provisions described in “Additional Provisions—Reference Rate” above.

Risks Relating to the Reference Rate

￭The reference rate will be affected by a number of factors. A number of factors can affect the reference rate, including, but not limited to:

￭sentiment regarding the U.S. and global economies;

￭expectations regarding the level of price inflation;

￭sentiment regarding credit quality in the U.S. and global credit markets;

￭central bank policy regarding interest rates;

￭inflation and expectations concerning inflation; and

￭performance of capital markets.

These and other factors may have a negative impact on the amount of interest payable on the notes and on the value of the notes prior to maturity.

￭The reference rate and the manner in which it is calculated may change in the future. There can be no assurance that the method by which the reference rate is calculated will continue in its current form. The reference rate may be altered or discontinued or the calculation or dissemination of the reference rate may be suspended. No person has any obligation to consider your interests in calculating, adjusting, converting, revising or discontinuing the reference rate. Any of these events could reduce the reference rate and may have a negative impact on the amount of interest payable on the notes and on the value of the notes prior to maturity.

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Use of Proceeds and Hedging

The proceeds from the sale of the notes will be used by us for general corporate purposes. We will receive, in aggregate, $1,000 per note issued, because, when we enter into hedging transactions in order to meet our obligations under the notes, our hedging counterparty will reimburse the cost of the agent’s commissions. The costs of the notes borne by you and described beginning on page 3 above comprise the agent’s commissions and the cost of issuing, structuring and hedging the notes.

Supplemental Information Concerning Plan of Distribution; Conflicts of Interest

Morgan Stanley or one of our affiliates will pay varying discounts and commissions to dealers, including Morgan Stanley Smith Barney LLC (“Morgan Stanley Wealth Management”) and their financial advisors, of up to $ per note depending on market conditions. The agent may distribute the notes through Morgan Stanley Wealth Management, as selected dealer, or other dealers, which may include Morgan Stanley & Co. International plc (“MSIP”) and Bank Morgan Stanley AG. Morgan Stanley Wealth Management, MSIP and Bank Morgan Stanley AG are affiliates of ours.

MS & Co. is an affiliate of MSFL and a wholly owned subsidiary of Morgan Stanley, and it and other affiliates of ours expect to make a profit by selling, structuring and, when applicable, hedging the notes. When MS & Co. prices this offering of notes, it will determine the economic terms of the notes such that for each note the estimated value on the pricing date will be no lower than the minimum level described in “The Notes” on page 3.

MS & Co. will conduct this offering in compliance with the requirements of FINRA Rule 5121 of the Financial Industry Regulatory Authority, Inc., which is commonly referred to as FINRA, regarding a FINRA member firm’s distribution of the securities of an affiliate and related conflicts of interest. MS & Co. or any of our other affiliates may not make sales in this offering to any discretionary account.

Acceleration Amount in Case of an Event of Default

In case an event of default with respect to the notes shall have occurred and be continuing, the amount declared due and payable per note upon any acceleration of the notes shall be an amount in cash equal to the stated principal amount plus accrued and unpaid interest.

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Tax Considerations

In the opinion of our counsel, Davis Polk & Wardwell LLP, the notes should be treated as “variable rate debt instruments” for U.S. federal tax purposes, and the remainder of this discussion assumes this treatment is correct.

The treatment of the notes depends on whether the initial fixed rate is within 0.25% of the floating rate on the issue date.

If the notes were issued on October 6, 2025, we would treat them as “variable debt instruments” providing for a single fixed rate followed by a single qualified inverse floating rate (“QIFR”), as described in the sections of the accompanying prospectus supplement called “United States Federal Taxation—Tax Consequences to U.S. Holders—Notes—Floating Rate Notes—General” and “—Floating Rate Notes that Provide for Multiple Rates,” because we have determined that the initial fixed rate was not within 0.25% of the floating rate on that date. Unless otherwise stated, the following discussion in this paragraph is based on the treatment of each note as described in the preceding sentence. Under applicable Treasury Regulations, in order to determine the amount of qualified stated interest (“QSI”) and original issue discount (“OID”) in respect of the notes, an equivalent fixed rate debt instrument must be constructed. The equivalent fixed rate debt instrument is constructed in the following manner: (i) first, the initial fixed rate is converted to a QIFR that would preserve the fair market value of the notes, and (ii) second, each QIFR (including the QIFR determined under (i) above) is converted to a fixed rate substitute (which will generally be the value of that QIFR as of the issue date of the notes). The rules under “United States Federal Taxation—Tax Consequences to U.S. Holders—Notes—Discount Notes—General” must be applied to the equivalent fixed rate debt instrument to determine the amounts of QSI and OID on the notes. Under this method, the notes may be issued with OID.

Alternatively, if the initial fixed rate is within 0.25% of the floating rate on the issue date, the notes should instead be treated as providing for a single QIFR. In such case, the notes should not be treated as issued with OID and all of the interest paid on the notes should be treated as QSI.

A U.S. holder is required to include any QSI in income in accordance with the U.S. holder’s regular method of accounting for U.S. federal income tax purposes. U.S. holders will be required to include OID in income for U.S. federal income tax purposes as it accrues, in accordance with a constant yield method based on a compounding of interest. QSI allocable to an accrual period must be increased (or decreased) by the amount, if any, which the interest actually accrued or paid during an accrual period (including the fixed rate payments made during the initial period) exceeds (or is less than) the interest assumed to be accrued or paid during the accrual period under the equivalent fixed rate debt instrument. For the QSI and the amount of OID (if any) on a note, please contact Morgan Stanley at [email protected].

If you are a non-U.S. holder, please read the section of the accompanying prospectus supplement called “United States Federal Taxation—Tax Consequences to Non-U.S. Holders.”

Both U.S. and non-U.S. holders should read the section of the accompanying prospectus supplement entitled “United States Federal Taxation.”

You should consult your tax adviser regarding all aspects of the U.S. federal tax consequences of an investment in the notes, as well as any tax consequences arising under the laws of any state, local or non-U.S. taxing jurisdiction. Moreover, neither this document nor the accompanying prospectus supplement addresses the consequences to taxpayers subject to special tax accounting rules under Section 451(b) of the Internal Revenue Code of 1986, as amended.

The discussion in the preceding paragraphs under “Tax Considerations,” and the discussion contained in the section entitled “United States Federal Taxation” in the accompanying prospectus supplement, insofar as they purport to describe provisions of U.S. federal income tax laws or legal conclusions with respect thereto, constitute the full opinion of Davis Polk & Wardwell LLP regarding the material U.S. federal tax consequences of an investment in the notes.

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Where You Can Find More Information

MSFL and Morgan Stanley have filed a registration statement (including a prospectus, as supplemented by a prospectus supplement) with the Securities and Exchange Commission, or SEC, for the offering to which this communication relates. You should read the prospectus in that registration statement, the prospectus supplement and any other documents relating to this offering that MSFL and Morgan Stanley have filed with the SEC for more complete information about MSFL, Morgan Stanley and this offering. When you read the accompanying prospectus supplement, please note that all references in such supplement to the prospectus dated November 16, 2023, or to any sections therein, should refer instead to the accompanying prospectus dated April 12, 2024 or to the corresponding sections of such prospectus, as applicable. You may get these documents without cost by visiting EDGAR on the SEC web site at.www.sec.gov. Alternatively, MSFL, Morgan Stanley, any underwriter or any dealer participating in the offering will arrange to send you the prospectus and the prospectus supplement if you so request by calling toll-free 1-800-584-6837.

You may access these documents on the SEC web site at www.sec.gov. as follows:

Prospectus Supplement dated November 16, 2023

Prospectus dated April 12, 2024

Terms used but not defined in this document are defined in the prospectus supplement or in the prospectus.

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