RBB Bancorp

Item 8.01 Other Events. Common Stock Repurchase Plan Authorization The Board of Directors of RBB Bancorp (the “Company”) has authorized the repurchase of up to 1 million shares of the Company’s outstanding common stock through June 30, 2028 (the “Repurchase Plan”). The Repurchase Plan represents a dollar amount of approximately $25 million, based on the Company’s current stock price, and represents approximately 6% of the Company’s current outstanding shares. The Repurchase Plan permits shares to be purchased in open market or private transactions, through block trades, and pursuant to any trading plan that may be adopted in accordance with Rules 10b5-1 and 10b-18 of the Securities and Exchange Commission. The authorized Repurchase Plan 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 Plan does not obligate the Company to purchase any particular number of shares. Partial Redemption of 4.00% Fixed-to-Floating Rate Subordinated Notes due 2031 On June 12, 2026, the Company notified Wilmington Trust, National Association, as paying agent (the “Paying Agent”), of the Company’s intention to redeem (the “Redemption”), on July 1, 2026 (the “Redemption Date”), $40.0 million aggregate principal amount of its outstanding 4.00% Fixed-to-Floating Rate Subordinated Notes due 2031, originally issued on March 26, 2021 (the “Notes”). On April 1, 2026, the 4.00% fixed interest rate reset to a floating rate equal to three-month term SOFR plus a spread of 329 basis points, which equaled 6.98% on that date. The Notes will be redeemed at a cash redemption price equal to 100% of the aggregate principal amount of the Notes being redeemed, plus accrued and unpaid interest thereon, but excluding the Redemption Date (the “Redemption Price”), or approximately $40.7 million in aggregate. Upon completion of the Redemption, $80.0 million aggregate principal amount of the Notes will remain outstanding and the interest rate will reset on July 1, 2026 to the then three-month term SOFR plus a spread of 329 basis points. Payment of the Redemption Price will be made on the Redemption Date only upon presentation and surrender of the Notes to the Paying Agent. Interest on the Notes called for redemption will cease to accrue on and after the Redemption Date. Notice of redemption will be delivered to the registered holders of the Notes in accordance with the terms governing the Notes.