X0508 4 2025-05-20 false 0000902791 BARRETT BUSINESS SERVICES INC BBSI 0001257908 CARLEY THOMAS J 8100 NE PARKWAY DRIVE, SUITE 200 VANCOUVER WA 98662 true false false false false Common Stock 2025-05-20 4 M false 12354.00 9.95 A 103982.00 D Common Stock 2025-05-20 4 S false 12354.00 42.6011 D 91628.00 D Common Stock 12008.00 I By Spouse Employee Stock Options (Right to Buy) 9.95 2025-05-20 4 M false 12354.00 0.00 D 2026-07-01 Common Stock 12354.00 12646.00 D Represents the exercise of this option award ahead of its expiration in July 2026. This transaction was executed in multiple trades at prices ranging from $42.50 to $42.835. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. Became exercisable in four equal installments beginning July 1, 2017. /s/ Anthony Harris, as attorney-in-fact 2025-05-22