X0609 4 2026-03-31 0001624322 Business First Bancshares, Inc. BFST 0001927057 Manning Kathryn false 500 LAUREL STREET, SUITE 101 BATON ROUGE LA 70801 1 EVP & Chief Risk Officer 0 COMMON STOCK 2026-03-31 4 F 0 874 27.04 D 15791 D Restricted Stock Units 0.0000 Common Stock 8641 8641 D Includes: (a) 2,395 time-based restricted stock units granted to the reporting person on December 12, 2024, which will vest in two substantially equal installments on the second and third anniversary of the issuance date; (b) 2,517 time-based restricted stock units granted to the reporting person on March 1, 2025, which will vest in two substantially equal installments on the second and third anniversary of the issuance date; (c) 745 time-based restricted stock units granted to the reporting person on March 2, 2026, which will vest in three substantially equal installments on the first, second, and third anniversary of the issuance date; and (d) 2,984 time-based restricted stock units, which will vest in three substantially equal installments on the first, second, and third anniversary of the issuance date. /s/ Heather Roemer, as attorney-in-fact for Kathryn Manning 2026-04-02