X0306 4 2022-03-31 0001624322 Business First Bancshares, Inc. BFST 0001810642 Lee Margaret Singer 500 LAUREL STREET, SUITE 101 BATON ROUGE LA 70801 1 EVP,Chief HR Officer of b1BANK Common Stock 2022-03-31 4 F 0 1256 24.33 D 9545 D Includes (a) 1,655 shares of unvested restricted stock granted on 2/1/2021, which will vest on 3/31/2023, and (b) 2,880 shares of unvested restricted stock granted on 2/1/2022, of which 1,439 shares will vest on 3/31/2023 and the remaining 1,441 shares will vest on 3/31/2024. 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. /s/ Heather Roemer, as attorney-in-fact for Margaret Singer Lee 2022-04-04