Form 424B2 MORGAN STANLEY –

Callable Contingent Income Buffered Securities due June 13, 2025

Payments on the Securities Based on the Worst Performing of the iShares® MSCI Emerging Markets ETF, the Russell 2000® Index and the EURO STOXX 50® Index

Fully and Unconditionally Guaranteed by Morgan Stanley

Principal at Risk Securities

The securities offered are unsecured obligations of Morgan Stanley Finance LLC (“MSFL”) and are fully and unconditionally guaranteed by Morgan Stanley. The securities have the terms described in the accompanying prospectus supplement, index supplement and prospectus, as supplemented or modified by this document. The securities do not guarantee the repayment of principal and do not provide for the regular payment of interest. The securities will pay a contingent monthly coupon but only if the closing level of each of the iShares® MSCI Emerging Markets ETF, the Russell 2000® Index and the EURO STOXX 50® Index on the related observation date is at or above 75% of its respective initial level, which we refer to as the respective coupon barrier level. If the closing level of any underlying is less than the coupon barrier level for such underlying on any observation date, we will pay no interest for the related monthly period. In addition, beginning on September 15, 2022, we will redeem the securities on any quarterly redemption date for a redemption payment equal to the sum of the stated principal amount plus any contingent monthly coupon otherwise due with respect to the related observation date, if and only if the output of a risk neutral valuation model on a business day that is at least 2 but no more than 5 business days prior to such redemption date, based on the inputs indicated under “Call feature” below, indicates that redeeming on such date is economically rational for us as compared to not redeeming on such date. An early redemption of the securities will not automatically occur based on the performance of the underlyings. At maturity, if the securities have not previously been redeemed and if the final level of each underlying has appreciated, has remained unchanged or has declined by an amount less than or equal to the buffer amount of 30%, the payment at maturity will be the stated principal amount and, if the final level of each of the underlyings is also greater than or equal to its respective coupon barrier level, the related contingent monthly coupon. If, however, the final level of any underlying has declined from its initial level by an amount greater than the buffer amount of 30%, investors will lose 1.4286% for every 1% decline of the worst performing underlying beyond the specified buffer amount. Accordingly, investors in the securities must be willing to accept the risk of losing their entire investment if any underlying declines by an amount greater than the buffer amount, and also the risk of not receiving any monthly coupons during the entire 3-year term of the securities. Because payments on the securities are based on the worst performing of the underlyings, a decline of more than 30% by any underlying will result in few or no contingent monthly coupons and/or a loss of your investment, even if the other underlyings have appreciated or have not declined as much. Investors will not participate in any appreciation in any underlying. The securities are for investors who are willing to risk their principal and seek an opportunity to earn interest at a potentially above-market rate and the limited protection provided by the buffer feature in exchange for the risk of receiving no monthly interest if any underlying closes below the coupon barrier level for such underlying on the observation dates, and the risk of an early redemption of the securities based on the output of a risk neutral valuation model. The securities are notes issued as part of MSFL’s Series A Global Medium-Term Notes program.

All payments are subject to our credit risk. If we default on our obligations, you could lose some or all of your investment. These securities 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) The securities will be sold only to investors purchasing the securities in fee-based advisory accounts.

(2) MS & Co. expects to sell all of the securities that it purchases from us to an unaffiliated dealer at a price of $ per security, for further sale to certain fee-based advisory accounts at the price to public of $1,000 per security. MS & Co. will not receive a sales commission with respect to the securities. See “Supplemental information regarding plan of distribution; conflicts of interest.” For additional information, see “Plan of Distribution (Conflicts of Interest)” in the accompanying prospectus supplement.

(3) See “Use of proceeds and hedging” on page 40.

The securities involve risks not associated with an investment in ordinary debt securities. See “Risk Factors” beginning on page 14.

The Securities and Exchange Commission and state securities regulators have not approved or disapproved these securities, or determined if this document or the accompanying prospectus supplement, index 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 prospectus supplement, index supplement and prospectus, each of which can be accessed via the hyperlinks below. Please also see “Additional Terms of the Securities” and “Additional Information About the Securities” at the end of this document.

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

Prospectus Supplement dated November 16, 2020 Index Supplement dated November 16, 2020 ​ Prospectus dated November 16, 2020