The number of large staffing firms in the US — those making $100 million or more in revenue — jumped 21%. Meanwhile, another company has joined the top five for the first time.

Released today, Staffing Industry Analysts’ annual list of Largest US Staffing Firms found that 225 companies had US staffing revenue of $100 million or more in 2021. That compares to 186 in last year’s report.

“While some industries experienced disruptions in 2021, the staffing industry instead flourished in an environment of record demand,” said Timothy Landhuis, VP of research at SIA. “We salute the hard work and resourcefulness of the staffing firms that appear on this year’s list, that were able to deliver at record scale, and that altogether generated an extraordinary $135 billion in staffing revenue.”

Allegis Group, based in Hanover, Maryland, ranked as the largest US staffing firm as it had on last year’s list. However, this year’s list featured a new firm in the No. 2 spot — Aya Healthcare, a San Diego-based healthcare staffing firm, up from No. 14 last year.

Click on chart to enlarge.

Five largest US staffing firms

IT temporary staffing was the largest revenue segment for 64 firms, or 38% of the total 225 listed. Industrial staffing was cited by 61 firms, or 27%, as their largest revenue source. Healthcare staffing was the largest revenue segment for another 61 firms.

California was home to the US headquarters of 23 firms on the list. It was followed by Georgia, headquarters for 20, and Florida, headquarters for 19.

Staffing revenue in the report includes temporary staffing, direct hire and retained search as well as temp-to-hire conversions. It does not include other types of workforce solutions ecosystem revenue such as MSP, RPO, payrolling or outplacement.

Revenue figures in the report represent SIA’s best estimation based on available information at the time of publication. The accuracy of estimates may vary depending on multiple factors, including firms’ willingness to provide or confirm information about their operations.

The full “Largest Staffing Firms in the United States: 2022 Update” report is available for SIA’s corporate and CWS Council members.