EXHIBIT 23.1

	Deloitte & Touche LLP
	1125 Northwest Couch Street
	Suite 600
	Portland, OR 97209-4156
	USA
	Tel:+1 503 222 1341
	Fax:+1 503 224 2172
	www.deloitte.com

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S-8 of our reports dated February 25, 2026, relating to the financial statements of Barrett Business Services, Inc. and the effectiveness of Barrett Business Services, Inc.’s internal control over financial reporting, appearing in the Annual Report on Form 10-K of Barrett Business Services, Inc. for the year ended December 31, 2025.

Portland, Oregon

June 12, 2026