Free Writing Prospectus (Form FWP)

Morgan Stanley Finance LLC

Structured Investments

Free Writing Prospectus to Preliminary Pricing Supplement No. 16,700

Filed pursuant to Rule 433

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

June 16, 2026

Issuer and guarantor

Morgan Stanley Finance LLC (issuer) and Morgan Stanley (guarantor)

Market measure

An equally weighted basket (the "Basket") composed of the following basket components, with the weightings noted parenthetically: the common stock of Oracle Corporation (the "ORCL Stock") (50%) and the common stock of Micron Technology, Inc. (the "MU Stock") (50%) (each referred to as a "basket component")

Pricing date*

June 29, 2026

Original issue date*

July 2, 2026

Face amount

$1,000 per security

Contingent coupon payments (with memory feature)

On each contingent coupon payment date, you will receive a contingent coupon payment at a per annum rate equal to the contingent coupon rate if, and only if, the basket closing level on the related calculation day is greater than or equal to the coupon threshold level.

Each "contingent coupon payment," if any, will be calculated per security as follows:

($1,000 × contingent coupon rate) / 12.

In addition, if the basket closing level on one or more calculation days is less than the coupon threshold level and, on a subsequent calculation day, the basket closing level is greater than or equal to the coupon threshold level, the securities will pay the contingent coupon payment due for the subsequent calculation day plus all previously unpaid contingent coupon payments (without interest accruing on amounts previously unpaid).

Contingent coupon rate

At least 17.25% per annum, to be determined on the pricing date

Automatic call

The securities are not subject to automatic call until approximately six months after the original issue date. Following this 6-month non-call period, if, on any calculation day (other than the final calculation day), beginning in December 2026, the basket closing level is greater than or equal to the starting level, the securities will be automatically called for a cash payment per security equal to the face amount plus a final contingent coupon payment and any previously unpaid contingent coupon payments on the related call settlement date.

Calculation days

Monthly, on the 28th of each month, commencing in July 2026 and ending on the final calculation day. We also refer to the June 2029 calculation day as the final calculation day.

Contingent coupon payment dates

Three business days after the applicable calculation day; provided that the coupon payment date for the final calculation day is the maturity date.

Call settlement date

Three business days after the applicable calculation day.

Maturity payment amount (per security)

if the ending level is greater than or equal to the downside threshold level:

$1,000; or

if the ending level is less than the downside threshold level:

$1,000 × (basket performance factor + buffer amount)

Basket closing level

The "basket closing level" will be equal to the product of (i) 100 and (ii) an amount equal to 1 plus the sum of: (A) 50% times the stock return of the ORCL Stock and (B) 50% times the stock return of the MU Stock.

Stock closing price

With respect to each basket component, stock closing price, closing price and adjustment factor have the meanings set forth under "General Terms of the Securities-Certain Terms for Securities Linked to an Underlying Stock-Certain Definitions" in the accompanying product supplement for principal at risk securities.

Initial stock price

For each basket component, its stock closing price on the pricing date.

Stock return:

On any calculation day for each basket component,

(stock closing price - initial stock price) / initial stock price

Maturity date*

July 3, 2029

Starting level

The basket closing level on the pricing date

Ending level

The basket closing level on the final calculation day

Basket performance factor

The ending level divided by the starting level.

Coupon threshold level

80, which is equal to 80% of the starting level

Downside threshold level

80, which is equal to 80% of the starting level

Buffer amount

20%

Calculation agent

Morgan Stanley & Co. LLC, an affiliate of the issuer

Denominations

$1,000 and any integral multiple of $1,000

Agent discount**

Morgan Stanley & Co. LLC and Wells Fargo Securities, LLC will act as the agents for this offering. Wells Fargo Securities, LLC will receive a commission of up to $23.25 for each security it sells. Dealers, including Wells Fargo Advisors ("WFA"), may receive a selling concession of up to $17.50 per security, and WFA may receive a distribution expense fee of $0.75 for each security sold by WFA.

CUSIP

61781GPS4

Tax considerations

See preliminary pricing supplement