Primary Offering Prospectus (Form 424B2)

June 2026

Preliminary Pricing Supplement No. 16,699

Registration Statement Nos. 333-293641; 333-293641-01

Dated June 15, 2026

Filed pursuant to Rule 424(b)(2)

Morgan Stanley Finance LLC

Structured Investments

Opportunities in U.S. Equities

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

Fully and Unconditionally Guaranteed by Morgan Stanley

The current estimated value of the securities is approximately $960.80 per security, or within $30.00 of that estimate. The estimated value of the securities is determined using our own pricing and valuation models, market inputs and assumptions relating to the underlyings, instruments based on the underlyings, 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. See "Estimated Value of the Securities" on page 3.

The securities have complex features and investing in the securities involves risks not associated with an investment in ordinary debt securities. See "Risk Factors" beginning on page 11. All payments on the securities are subject to our credit risk.

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

The securities 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.

You should read this document together with the related product supplement for principal at risk securities, index supplement, tax supplement and prospectus, each of which can be accessed via the hyperlinks below. Please also see "Additional Information About the Securities" at the end of this document.

As used in this document, "we," "us" and "our" refer to Morgan Stanley or MSFL, or Morgan Stanley and MSFL collectively, as the context requires.

(1) Wells Fargo Securities, LLC, an agent for this offering, will receive a commission of up to $28.25 for each security it sells. Dealers, including Wells Fargo Advisors ("WFA"), may receive a selling concession of up to $22.50 per security, and WFA will receive a distribution expense fee of $0.75 for each security sold by WFA. See "Supplemental information concerning plan of distribution; conflicts of interest."

(2) In respect of certain securities sold in this offering, we may pay a fee of up to $3.00 per security to selected securities dealers in consideration for marketing and other services in connection with the distribution of the securities to other securities dealers.

(3) See "Use of Proceeds and Hedging" in the accompanying product supplement.

Product Supplement for Principal at Risk Securities dated April8, 2026 ​Index Supplementdated April 8, 2026 TaxSupplementdated April 8, 2026 Prospectus dated April 8, 2026

Morgan Stanley Wells Fargo Securities

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

June 2026 Page 2

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

June 2026 Page 3

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

The considerations identified above are not exhaustive. Whether or not the securities are an appropriate investment for you will depend on your individual circumstances, and you should reach an investment decision only after you and your investment, legal, tax, accounting and other advisors have carefully considered the appropriateness of an investment in the securities in light of your particular circumstances. You should also review carefully the "Risk Factors" herein and in the accompanying product supplement and tax supplement for risks related to an investment in the securities. For more information about the underlyings, please see the sections titled "Dow Jones Industrial AverageSM Overview" and "S&P 500® Index Overview" below.

June 2026 Page 4

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

At maturity, the maturity payment amount per $1,000 face amount of securities will be determined as follows:

June 2026 Page 5

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

Payoff Diagram

The payoff diagram below illustrates the maturity payment amount on the securities based on a range of hypothetical underlying returns of the lowest performing underlying and the following terms:

June 2026 Page 6

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

The following scenario analysis and examples are provided for illustrative purposes only and are hypothetical. They do not purport to be representative of every possible scenario concerning increases or decreases in the levels of the underlyings relative to their respective starting levels. We cannot predict the ending levels of the underlyings on the calculation day. You should not take the scenario analysis and these examples as an indication or assurance of the expected performance of the underlyings. The numbers appearing in the examples below may have been rounded for ease of analysis. Notwithstanding anything to the contrary in the accompanying product supplement for principal at risk securities, the amount you will receive per $1,000 face amount of securities at maturity will be the maturity payment amount, defined and calculated as provided in this document. The following scenario analysis and examples illustrate the maturity payment amount on a hypothetical offering of the securities, based on the following terms*:

* The hypothetical starting level of 100 for the underlyings has been chosen for illustrative purposes only and does not represent the actual starting level of either underlying. The actual starting levels, threshold levels and maximum return will be determined on the pricing date and will be set forth under "Terms" above. For historical data regarding the actual closing levels of the underlyings, see the historical information set forth herein.

Example 1 - Each underlying appreciates over the term of the securities, and investors receive a positive return, calculated based on the underlying return of the lowest performing underlying.

In example 1, the ending level of each of the INDU Index and the SPX Index is greater than its starting level. The INDU Index has appreciated by 10% and the SPX Index has appreciated by 50%. Therefore, investors receive at maturity the face amount plus the lesser of a positive return equal to 150% of the appreciation of the lowest performing underlying, which is the INDU Index in this example, and the maximum return of $345. Investors receive $1,150 per security at maturity.

June 2026 Page 7

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

Example 2 - Each underlying appreciates over the term of the securities, and investors receive the maximum return, calculated based on the underlying return of the lowest performing underlying.

In example 2, the ending level of each of the INDU Index and the SPX Index is greater than its starting level. The INDU Index has appreciated by 100% and the SPX Index has appreciated by 50%. Therefore, investors receive at maturity the face amount plus the lesser of a positive return equal to 150% of the appreciation of the lowest performing underlying, which is the SPX Index in this example, and the maximum return of $345. Investors receive $1,345 per securities at maturity (which is the maximum maturity payment amount). The appreciation potential of the securities is limited by the hypothetical maximum return. Although the participation rate provides 150% exposure to any increase in the ending level of the lowest performing underlier over its starting level, because the maturity payment amount will be limited to 134.50% of the face amount for the securities (assuming a maximum return of $345 per security), any increase in the ending level over the starting level by more than approximately 23% of the starting level will not further increase the return on the securities.

Example 3 - One underlying appreciates, while the other underlying decline over the term of the securities but not below the hypothetical starting level by more than the buffer amount, and investors receive the face amount.

In example 3, the ending level of the INDU Index is greater than its starting level, while the ending level of the SPX is less than its starting level, but is greater than or equal to its threshold level. The INDU Index has appreciated by 30% while the SPX Index has declined by 7%. Investors will receive the face amount of $1,000.

Example 4 - One underlying appreciates while the other underlying declines over the term of the securities, and the ending level of the lowest performing underlying is less than the hypothetical starting level by more than the buffer amount. Investors are therefore exposed to the decline in the lowest performing underlying in excess of the buffer amount.

June 2026 Page 8

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

In example 4, the ending level of the INDU Index is greater than its starting level while the ending level of the SPX Index has declined below its threshold level. The INDU Index has appreciated by 30% while the SPX Index has depreciated by 70%. Because the ending level of the SPX Index has declined by more than the buffer amount, investors are exposed to the negative performance of the SPX Index, which is the lowest performing underlying in this example, in excess of the buffer amount. Investors receive a maturity payment amount of $500.

Example 5 - Each underlying declines below its respective threshold level, and investors are therefore exposed to the decline in the lowest performing underlying in excess of the buffer amount.

In example 5, the ending level of each of the INDU Index and the SPX Index is less than its respective threshold level. The INDU Index has declined by 70% and the SPX Index has declined by 60%. Therefore, investors are exposed to the negative performance of the INDU Index, which is the lowest performing underlying in this example, in excess of the buffer amount. Investors receive a maturity payment amount of $500.

Because the maturity payment amount of the securities is based on the lowest performing underlying, a decline in either underlying below its respective threshold level will result in a loss of up to 80% of the face amount of your securities at maturity, even if the other underlying has appreciated or has not declined as much.

June 2026 Page 9

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

Scenario Analysis - Hypothetical Maturity Payment Amount for each $1,000 Face Amount of Securities.

*The underlyings exclude cash dividend payments on stocks included in the underlyings.

(1) Assumes a maximum return of 34.50% of the face amount ($345 per security).

(2) The "Return on Securities" is the number, expressed as a percentage, which results from comparing the maturity payment amount per $1,000 face amount of securities to the purchase price of $1,000 per security.

(3) The hypothetical starting level of each underlying.

June 2026 Page 10

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

This section describes the material risks relating to the securities. For further discussion of these and other risks, you should read the section entitled "Risk Factors" in the accompanying product supplement for principal at risk securities, index supplement, tax supplement and prospectus. We also urge you to consult your investment, legal, tax, accounting and other advisers in connection with your investment in the securities.

Risks Relating to an Investment in the Securities

￭The securities do not pay interest, and you will receive less, and up to 80% less, than the face amount of your securities at maturity if the ending level of the lowest performing underlying is less than its respective threshold level. The terms of the securities differ from those of ordinary debt securities in that the securities do not pay interest or repay a fixed amount of the face amount of the securities. If the ending level of the lowest performing underlying is less than its threshold level, which is 80% of the starting level, you will receive less, and up to 80% less, than the face amount of your securities at maturity. Investors may lose some or a significant portion of their investment in the securities.

￭The appreciation potential of the securities is limited by the maximum return. The appreciation potential of the securities is limited by the maximum return. Although the participation rate provides 150% exposure to any increase in the ending levels of the lowest performing underlier over its starting level, because any positive return on the securities will be limited to the maximum return of at least 34.50% of the face amount for the securities (assuming a maximum maturity payment amount of $1,345 per security), any increase in the ending levels of the lowest performing underlier over its starting level by more than approximately 23% of its starting level will not further increase the return on the securities.

￭The market price will be influenced by many unpredictable factors. Several factors, many of which are beyond our control, will influence the value of the securities in the secondary market and the price at which MS & Co. or any other dealer may be willing to purchase or sell the securities in the secondary market, including the level, volatility (frequency and magnitude of changes in level) and dividend yield of the underlyings, interest and yield rates in the market, time remaining to maturity, geopolitical conditions and economic, financial, political, regulatory or judicial events that affect the underlyings or equities markets generally and which may affect the ending levels of the underlyings and any actual or anticipated changes in our credit ratings or credit spreads. Generally, the longer the time remaining to maturity, the more the market price of the securities will be affected by the other factors described above. The levels of the underlyings may be, and have recently been, volatile, and we can give you no assurance that the volatility will lessen. See "Dow Jones Industrial AverageSM Overview" and "S&P 500® Index Overview". You may receive less, and possibly significantly less, than the face amount per security if you try to sell your securities prior to maturity.

￭The securities 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 securities. You are dependent on our ability to pay all amounts due on the securities at maturity, and therefore you are subject to our credit risk. If we default on our obligations under the securities, your investment would be at risk and you could lose some or all of your investment. As a result, the market value of the securities 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 market value of the securities.

￭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

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Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

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 amount payable on the securities is not linked to the values of the underlyings at any time other than the calculation day. The ending level of each underlying will be based on the closing level of such underlying on the calculation day, subject to postponement for non-trading days and certain market disruption events. Even if each underlying appreciates prior to the calculation day but the level of either underlying decreases by the calculation day, the maturity payment amount will be less, and may be significantly less, than it would have been had the maturity payment amount been linked to the levels of the underlyings prior to such decrease. Although the actual levels of the underlyings on the maturity date or at other times during the term of the securities may be higher than their respective ending levels, the maturity payment amount will be based solely on the closing levels of the underlyings on the calculation day.

￭Investing in the securities is not equivalent to investing in the underlyings. Investing in the securities is not equivalent to investing in the underlyings or the component stocks or either underlying. Investors in the securities will not have voting rights or rights to receive dividends or other distributions or any other rights with respect to the stocks that constitute either underlying.

￭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 securities in the face amount reduce the economic terms of the securities, cause the estimated value of the securities to be less than the face amount 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., may be willing to purchase the securities in secondary market transactions will likely be significantly lower than the face amount, because secondary market prices will exclude the issuing, selling, structuring and hedging-related costs that are included in the face amount 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 as well as other factors.

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

However, because the costs associated with issuing, selling, structuring and hedging the securities are not fully deducted upon issuance, for a period of up to 3 months following the issue date, to the extent that MS & Co. may buy or sell the securities in the secondary market, absent changes in market conditions, including those related to the underlyings, and to our secondary market credit spreads, it would do so based on values higher than the estimated value, and we expect that those higher values will also be reflected in your brokerage account statements.

￭The estimated value of the securities 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 securities than those generated by others, including other dealers in the market, if they attempted to value the securities. 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 securities in the secondary market (if any exists) at any time. The value of your securities at any time after the date of this document will vary based on many factors that cannot be predicted with accuracy, including our creditworthiness and changes in market conditions. See also "The market price will be influenced by many unpredictable factors" above.

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Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

￭The securities will not be listed on any securities exchange and secondary trading may be limited. The securities will not be listed on any securities exchange. Therefore, there may be little or no secondary market for the securities. MS & Co. and WFS may, but are not obligated to, make a market in the securities and, if either of them once chooses to make a market, may cease doing so at any time. When they do make a market, they will generally do so for transactions of routine secondary market size at prices based on their respective estimates of the current value of the securities, taking into account their respective bid/offer spreads, 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 they will be able to resell the securities. Even if there is a secondary market, it may not provide enough liquidity to allow you to trade or sell the securities easily. Since other broker-dealers may not participate significantly in the secondary market for the securities, the price at which you may be able to trade your securities is likely to depend on the price, if any, at which MS & Co. or WFS is willing to transact. If, at any time, MS & Co. and WFS were to cease making a market in the securities, it is likely that there would be no secondary market for the securities. Accordingly, you should be willing to hold your securities to maturity.

￭The calculation agent, which is a subsidiary of Morgan Stanley and an affiliate of MSFL, will make determinations with respect to the securities. As calculation agent, MS & Co. will determine the starting levels, the threshold levels and the ending levels and will calculate the amount of cash you receive at maturity, if any. Moreover, certain determinations made by MS & Co., in its capacity as calculation agent, may require it to exercise discretion and make subjective judgments, such as with respect to the occurrence or non-occurrence of market disruption events and the selection of a successor index or calculation of an ending level in the event of a market disruption event or discontinuance of any of the underlyings. These potentially subjective determinations may adversely affect the payout to you at maturity, if any. For further information regarding these types of determinations, see "General Terms of the Securities-Market Disruption Events," "-Adjustments to an Index," "-Discontinuance of an Index," "-Consequences of a Market Disruption Event; Postponement of a Calculation Day" and "Alternate Exchange Calculation in Case of an Event of Default" in the accompanying product supplement for principal at risk securities. In addition, MS & Co. has determined the estimated value of the securities on the pricing date.

￭Hedging and trading activity by our affiliates could potentially adversely affect the value of the securities. One or more of our affiliates and/or third-party dealers expect to carry out hedging activities related to the securities (and possibly to other instruments linked to the underlyings or the component stocks of the underlyings), including trading in the stocks that constitute the underlyings as well as in other instruments related to the underlyings. As a result, these entities may be unwinding or adjusting hedge positions during the term of the securities, and the hedging strategy may involve greater and more frequent dynamic adjustments to the hedge as the calculation day approaches. Some of our affiliates also trade the stocks that constitute the underlyings and other financial instruments related to the underlyings on a regular basis as part of their general broker-dealer and other businesses. Any of these hedging or trading activities on or prior to the pricing date could potentially affect the starting level of an underlying, and, therefore, could increase the level at or above which such underlying must close on the calculation day so that investors do not suffer a significant loss on their initial investment in the securities (depending also on the performance of the other underlying). Additionally, such hedging or trading activities during the term of the securities, including on the calculation day, could adversely affect the level of an underlying on the calculation day, and, accordingly, the amount of cash an investor will receive at maturity, if any (depending also on the performance of the other underlying).

￭The maturity date may be postponed if the calculation day is postponed. If the scheduled calculation day is not a trading day or if a market disruption event occurs on that day so that the calculation day is postponed and falls less than three business days prior to the maturity date, the maturity date of the securities will be postponed to the third business day following that calculation day as postponed.

￭Potentially inconsistent research, opinions or recommendations by Morgan Stanley, MSFL, WFS or our or their respective affiliates. Morgan Stanley, MSFL, WFS and our or their respective affiliates may publish research from time to time on financial markets and other matters that may influence the value of the securities, or express opinions or provide recommendations that are inconsistent with purchasing or holding the securities. Any research, opinions or recommendations expressed by Morgan Stanley, MSFL, WFS or our or their respective affiliates may not be consistent with each other and may be modified from time to time without notice. Investors should make

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Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

their own independent investigation of the merits of investing in the securities and the underlyings to which the securities are linked.

￭The U.S. federal income tax consequences of an investment in the securities offered by this pricing supplement are uncertain. There is no direct legal authority regarding the proper U.S. federal income tax treatment of the securities, and significant aspects of the tax treatment of the securities are uncertain. You should review carefully the section entitled "United States Federal Income Tax Considerations" herein, in combination with the section entitled "United States Federal Taxation" in the accompanying tax supplement, and consult your tax adviser regarding the U.S. federal income tax consequences of an investment in the securities.

Risks Relating to the Underlyings

￭You are exposed to the price risk of each underlying. Your return on the securities is not linked to a basket consisting of each underlying. Rather, it will be based upon the independent performance of each underlying. Unlike an instrument with a return linked to a basket of underlying assets, in which risk is mitigated and diversified among all the components of the basket, you will be exposed to the risks related to each underlying. Poor performance by either underlying over the term of the securities will negatively affect your return and will not be offset or mitigated by any positive performance by the other underlying. If either underlying has declined to below its respective threshold level as of the calculation day, you will be exposed to the negative performance of the lowest performing underlying at maturity, even if the other underlying has appreciated or has not declined as much, and you will lose a significant portion or all of your investment. Accordingly, your investment is subject to the price risk of each underlying.

￭Because the securities are linked to the performance of the lowest performing underlying, you are exposed to greater risk of sustaining a significant loss on your investment than if the securities were linked to just one underlying. The risk that you will suffer a significant loss on your investment is greater if you invest in the securities as opposed to substantially similar securities that are linked to the performance of just one underlying. With two underlyings, it is more likely that either underlying will decline to below its threshold level as of the calculation day, than if the securities were linked to only one underlying. Therefore it is more likely that you will suffer a significant loss on your investment.

￭Adjustments to the underlyings could adversely affect the value of the securities. The publisher of either underlying may add, delete or substitute the stocks constituting such underlying or make other methodological changes that could change the value of such underlying. The publisher of such underlying may discontinue or suspend calculation or publication of such underlying at any time. In these circumstances, the calculation agent will have the sole discretion to substitute a successor underlying that is comparable to the discontinued underlying and is permitted to consider indices that are calculated and published by the calculation agent or any of its affiliates. If the calculation agent determines that there is no appropriate successor underlying, the maturity payment amount on the securities will be an amount based on the closing prices at maturity of the securities composing such underlying at the time of such discontinuance, without rebalancing or substitution, computed by the calculation agent in accordance with the formula for calculating such underlying last in effect prior to discontinuance of the underlying.

￭Historical levels of the underlyings should not be taken as an indication of the future performance of the underlyings during the term of the securities. No assurance can be given as to the level of the underlyings at any time, including on the calculation day, because historical levels of the underlyings do not provide an indication of future performance of the underlyings.

June 2026 Page 14

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

The Dow Jones Industrial AverageSM is a price-weighted index composed of 30 common stocks that is published by S&P® Dow Jones Indices LLC, the marketing name and a licensed trademark of CME Group Inc., as representative of the broad market of U.S. industry. For additional information about the Dow Jones Industrial AverageSM, see the information set forth under "Dow Jones Industrial AverageSM" in the accompanying index supplement.

The following graph sets forth the daily closing levels of the INDU Index for the period from January 1, 2021 through June 11, 2026. The closing level of the INDU Index on June 11, 2026 was 50,848.75. We obtained the information in the graph below from Bloomberg Financial Markets without independent verification. The INDU Index has at times experienced periods of high volatility. You should not take the historical levels of the INDU Index as an indication of its future performance, and no assurance can be given as to the closing level of the INDU Index on the calculation day.

"Dow Jones," "Dow Jones Industrial Average," "Dow Jones Indexes" and "DJIA" are service marks of Dow Jones Trademark Holdings LLC. For more information, see "Dow Jones Industrial AverageSM" in the accompanying index supplement.

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Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

The S&P 500® Index, which is calculated, maintained and published by S&P® Dow Jones Indices LLC ("S&P®"), is intended to provide a benchmark for performance measurement of the large capitalization segment of the U.S. equity markets by tracking the stock price movement of 500 companies with large market capitalizations. Component stocks of the S&P 500® Index are required to have a total company level market capitalization that reflects approximately the 85th percentile of the S&P® Total Market Index. The S&P 500® Index measures the relative performance of the common stocks of 500 companies as of a particular time as compared to the performance of the common stocks of 500 similar companies during the base period of the years 1941 through 1943. For additional information about the S&P 500® Index, see the information set forth under "S&P® U.S. Indices-S&P 500® Index" in the accompanying index supplement.

The following graph sets forth the daily closing levels of the SPX Index for the period from January 1, 2021 through June 11, 2026. The closing level of the SPX Index on June 11, 2026 was 7,394.30. We obtained the information in the graph below from Bloomberg Financial Markets without independent verification. The SPX Index has at times experienced periods of high volatility. You should not take the historical levels of the SPX Index as an indication of its future performance, and no assurance can be given as to the closing level of the SPX Index on the calculation day.

"Standard & Poor's®," "S&P®," "S&P 500®," "Standard & Poor's 500" and "500" are trademarks of Standard and Poor's Financial Services LLC. For more information, see "S&P® U.S. Indices" in the accompanying index supplement.

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Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

Minimum ticketing size

$1,000 / 1 security

United States federal income tax considerations

You should review carefully the section in the accompanying tax supplement entitled "United States Federal Taxation." The following discussion, when read in combination with that section, constitutes the full opinion of our counsel, Davis Polk & Wardwell LLP, regarding the material U.S. federal income tax consequences of owning and disposing of the securities offered by this pricing supplement.

Generally, this discussion assumes that you purchased a security for cash in the original issuance at the stated issue price and does not address other circumstances specific to you, including consequences that may arise due to any other investments relating to an underlier. Moreover, as discussed in the section entitled "United States Federal Taxation" in the accompanying tax supplement, we have not attempted to ascertain whether any issuer of any underlier to which the securities relate is a U.S. real property holding corporation or a passive foreign investment company. You should consult your tax adviser regarding these issues, including the effect any circumstances specific to you may have on the U.S. federal income tax consequences of your ownership of a security.

In the opinion of our counsel, which is based on current market conditions, it is reasonable to treat the securities for U.S. federal income tax purposes as prepaid financial contracts that are "open transactions," as described in the section entitled "United States Federal Taxation-Tax Consequences to U.S. Holders-Program Securities Treated as Prepaid Financial Contracts that are Open Transactions" in the accompanying tax supplement. There is uncertainty regarding this treatment, and the Internal Revenue Service (the "IRS") or a court might not agree with it. Moreover, because this treatment of the securities and our counsel's opinion are based on market conditions as of the date of this preliminary pricing supplement, each is subject to confirmation on the pricing date. A different tax treatment could be adverse to you. Generally, if this treatment is respected, (i) you should not recognize taxable income or loss prior to the taxable disposition of your securities (including upon maturity or an earlier redemption, if applicable) and (ii) the gain or loss on your securities generally should be treated as capital gain or loss.

We do not plan to request a ruling from the IRS regarding the treatment of the securities. An alternative characterization of the securities could materially and adversely affect the tax consequences of ownership and disposition of the securities, including the timing and character of income recognized. In addition, the U.S. Treasury Department and the IRS have requested comments on various issues regarding the U.S. federal income tax treatment of "prepaid forward contracts" and similar financial instruments and have indicated that such transactions may be the subject of future regulations or other guidance. Furthermore, members of Congress have proposed legislative changes to the tax treatment of derivative contracts. Any legislation, Treasury regulations or other guidance promulgated after consideration of these issues could materially and adversely affect the tax consequences of an investment in the securities, possibly with retroactive effect.

Non-U.S. Holders. If you are a Non-U.S. Holder (as defined in the accompanying tax supplement), please also read the section entitled "United States Federal Taxation-Tax Consequences to Non-U.S. Holders-Program Securities Not Treated as Debt Instruments" in the accompanying tax supplement.

As discussed under "United States Federal Taxation-Tax Consequences to Non-U.S. Holders-Dividend Equivalents under Section 871(m) of the Code" in the accompanying tax supplement, Section 871(m) of the Internal Revenue Code and Treasury regulations promulgated thereunder ("Section 871(m)") generally impose a 30% withholding tax on dividend equivalents paid or deemed paid to Non-U.S. Holders with respect to certain financial instruments linked to U.S. equities or indices that include U.S. equities. The Treasury regulations, as modified by an IRS notice, exempt financial instruments issued prior to January 1, 2027 that do not have a "delta" of one. Based on certain determinations made by us, we expect that Section 871(m) will not apply to the securities with regard to Non-U.S. Holders. Our determination is not binding on the IRS, and the IRS may disagree with this determination. If necessary, further information regarding the potential application of Section 871(m) will be provided in the final pricing supplement for the securities.

We will not be required to pay any additional amounts with respect to U.S. federal withholding taxes.

You should consult your tax adviser regarding the U.S. federal income tax consequences of an investment in the securities, including possible alternative treatments, as well as tax consequences arising under the laws of any state, local or non-U.S. taxing jurisdiction.

June 2026 Page 17

Morgan Stanley Finance LLC

Market Linked Securities-Leveraged Upside Participation to a Cap and Fixed Percentage Buffered Downside

Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial AverageSM and the S&P 500® Index due June 22, 2029

Additional considerations

Client accounts over which Morgan Stanley, Morgan Stanley Wealth Management or any of their respective subsidiaries have investment discretion are not permitted to purchase the securities, either directly or indirectly.

Supplemental information regarding plan of distribution; conflicts of interest

MS & Co. and WFS will act as the agents for this offering. WFS will receive a commission of up to $28.25 for each security it sells. WFS proposes to offer the securities in part directly to the public at the price to public set forth on the cover page of this document and in part to Wells Fargo Advisors ("WFA") (the trade name of the retail brokerage business of WFS's affiliates, Wells Fargo Clearing Services, LLC and Wells Fargo Advisors Financial Network, LLC), an affiliate of WFS, or other securities dealers at such price less a selling concession of up to $22.50 per security. In addition to the selling concession allowed to WFA, WFS will pay $0.75 per security of the commission to WFA as a distribution expense fee for each security sold by WFA.

In addition, in respect of certain securities sold in this offering, we may pay a fee of up to $3.00 per security to selected securities dealers in consideration for marketing and other services in connection with the distribution of the securities to other securities dealers.

See "Plan of Distribution, Conflicts of Interest" in the accompanying product supplement for principal at risk securities for information about the distribution arrangements for the securities. References therein to "agent" refer to each of MS & Co. and WFS, as agents for this offering, except that references to "agent" in the context of offers to certain Morgan Stanley dealers and compliance with FINRA Rule 5121 do not apply to WFS. MS & Co., WFS or their affiliates may enter into hedging transactions with us in connection with this offering.

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 securities. When MS & Co. prices this offering of securities, it will determine the economic terms of the securities, including the maximum return, such that for each security the estimated value on the pricing date will be no lower than the minimum level described in "Estimated Value of the Securities" beginning 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. See "Plan of Distribution (Conflicts of Interest)" and "Use of Proceeds and Hedging" in the accompanying product supplement for principal at risk securities.

Where you can find more information

Morgan Stanley and MSFL have filed a registration statement (including a prospectus, as supplemented by the product supplement for principal at risk securities, the index supplement, and the tax 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 product supplement for principal at risk securities, the index supplement, the tax supplement and any other documents relating to this offering that Morgan Stanley and MSFL have filed with the SEC for more complete information about Morgan Stanley, MSFL and this offering. You may get these documents without cost by visiting EDGAR on the SEC web site at.www.sec.gov. Alternatively, Morgan Stanley, MSFL, any underwriter or any dealer participating in the offering will arrange to send you the product supplement for principal at risk securities, index supplement, tax supplement and prospectus 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:

Product Supplement for Principal at Risk Securities dated April 8, 2026

Index Supplement dated April 8, 2026

TaxSupplement dated April 8, 2026

Prospectus dated April 8, 2026

Terms used but not defined in this document are defined in the product supplement for principal at risk securities, in the index supplement, in the tax supplement or in the prospectus.

June 2026 Page 18