X0508 4/A 2024-12-12 2024-12-16 0001624322 Business First Bancshares, Inc. BFST 0001734773 MANSFIELD KEITH 500 LAUREL STREET, SUITE 101 BATON ROUGE LA 70801 1 EVP&COO of b1Bank 0 COMMON STOCK 83363 D Restricted Stock Units 0 2024-12-12 4 A 0 5555 0 A Common Stock 5555 5555 D No transaction is being reported at this time. This line is only reporting holdings as of December 16, 2024. Includes (a) 5,500 shares of unvested restricted stock granted on 2/1/2023 which will vest on 3/31/2025; and (b) 7,442 shares of unvested restricted stock granted on 2/1/2024, of which 3,666 shares will vest on 3/31/2025, and the remaining 3,776 shares will vest on 3/31/2026. Under the terms of the relevant restricted stock grants, the reported shares of unvested restricted stock are subject to forfeiture upon the occurrence of certain events. Includes 5,000 shares of the issuer's common stock held by reporting person's IRA. The original Form 4, filed on December 16, 2024, incorrectly reported the grant of the reported securities as an acquisition of shares of restricted stock under Table I. This amendment is being filed to correct the original report by reporting the grant of the reported securities as an acquisition of restricted stock units under Table II. Reflects the grant of 5,555 time-based restricted stock units granted to the reporting person under the Business First Bancshares, Inc. 2024 Equity Incentive Plan on December 12, 2024. The time-based restricted stock units will vest in three substantially equal installments on the first, second and third anniversary of the issuance date. Each time-based restricted stock unit is economically equivalent to one share of common stock of the issuer. Under the terms of the relevant restricted stock unit grant, the reported unvested restricted stock units are subject to forfeiture upon the occurrence of certain events. /s/ Heather Roemer, as attorney-in-fact for Keith Mansfield 2025-03-19