Material Event (Form 8-K)

MOUNTLAKE TERRACE, WA - August 24, 2026 - FS Bancorp, Inc. (NASDAQ: FSBW) ("Company"), the holding company for 1st Security Bank of Washington ("Bank") announced that its Board of Directors has authorized a share repurchase program of up to $5.0 million in shares of the Company's outstanding common stock in the open market, in privately negotiated transactions from time to time over a 12-month period until August 24, 2027, at such prices as may be determined by the Company's management. The repurchase program will commence no sooner than the second trading day after the public announcement of this repurchase program.

The repurchase program permits shares to be repurchased in open market or private transactions or pursuant to a trading plan adopted in accordance with Rule 10b5-1 of the Securities and Exchange Commission ("SEC").

Repurchases will be made at management's discretion at prices management considers to be attractive and in the best interests of both the Company and its shareholders, subject to the availability of stock, general market conditions, the trading price of the stock, alternative uses for capital, and the Company's financial performance. Open market purchases will be conducted in accordance with the limitations set forth in Rule 10b-18 of the SEC and other applicable legal requirements.

The repurchase program may be suspended, terminated or modified at any time for any reason, including market conditions, the cost of repurchasing shares, the availability of alternative investment opportunities, liquidity, and other factors deemed appropriate. These factors may also affect the timing and amount of share repurchases. The repurchase program does not obligate the Company to purchase any particular number of shares.

About FS Bancorp

FS Bancorp, Inc., a Washington corporation, is the holding company for 1st Security Bank of Washington. The Bank offers a range of loan and deposit services primarily to small- and middle-market businesses and individuals in Washington and Oregon. It operates through 33 bank branches, one headquarters office that provides loans and deposit services, and loan production offices in various suburban communities in the greater Puget Sound area, the Kennewick-Pasco-Richland metropolitan area of Washington, also known as the Tri-Cities, the greater Portland metropolitan area and in Vancouver, Washington. Additionally, the Bank services home mortgage customers across the Northwest, focusing on markets in Washington State including the Puget Sound, Tri-Cities, and Vancouver. Following the acquisition of Pacific West Bank, the Bank expanded its presence in the greater Portland market through locations in West Linn, Lake Oswego, Portland, and Vancouver.

For more information visit 1st Security Bank's website at www.fsbwa.com.