X0306 4/A 2018-06-13 2018-06-14 0001624322 Business First Bancshares, Inc. BFST 0001734773 MANSFIELD KEITH 500 LAUREL STREET, SUITE 101 BATON ROUGE LA 70801 1 EVP&COO of Business First Bank COMMON STOCK 2018-06-13 4 P 0 2000 25.12 A 9641 D COMMON STOCK 2018-06-14 4 P 0 8000 25.05 A 17641 D Includes (a) 233 shares of unvested restricted stock granted on 3/31/2017 and (b) 1,488 shares of unvested restricted stock granted on 3/31/2018, in each case subject to vesting in three equal installments over a period of two years beginning on the grant date and subject to the terms of the relevant restricted stock grant. The reported shares of unvested stock are subject to forfeiture upon the occurrence of certain events specified in the restricted stock grant. Includes 5,000 shares held by reporting person's IRA. /s/ David R. Melville, III, as attorney-in-fact 2018-06-18