Staffing agencies in St. Louis: the market on both sides of the river and how search fees work

This report is for job seekers and employers in the St. Louis region choosing an agency or search firm, and for B2B sellers whose customers are staffing firms on either side of the river.

St. Louis staffing agencies by the numbers

US Census Bureau, County Business Patterns 2023, St. Louis, MO-IL Metro Area (CBSA 41180), NAICS 56131 (Employment Placement Agencies and Executive Search Services) and 56132 (Temporary Help Services):

Two things stand out. Temp help holds 96% of the employees, because a temp agency is the employer of record for everyone it places: the Census definition says the workers supplied "are employees of the temporary help services establishment," so a branch staffing three warehouses reports the warehouse temps as its own staff. And executive search is a market of very small firms: 49 offices with 136 employees, under three each, most of them recruiters paid well.

Where they are

Two county totals carry the Census Bureau's high-noise flag (its confidentiality noise moved them 5% or more), so they're shown as not reported. St. Louis County is the center, with 58% of the locations. All 51 locations in the city of St. Louis are temp help; the city has no placement or search office in the data. Madison County's 24 locations average about 80 employees, the largest in the region.

How big they are

244 locations have fewer than 20 employees. The Census Bureau doesn't publish several larger classes for the two codes combined, but the temp help row is complete: 40 temp locations have 20 to 49 employees, 39 have 50 to 99, 47 have 100 to 249 and 12 have 250 to 499, and none has 500 or more. So at least 59 locations, all temp help, have 100 or more employees.

These are establishments with paid employees, not companies: a national brand's six St. Louis branches count six times, and independent recruiters with no payroll aren't counted. The 21 metro PEO locations sit in a different code and aren't included.

Types of agency, and which to use

For job seekers: register with agencies that place your kind of work, expect the agency to be your employer on any temp assignment, and don't pay a fee to be placed; employers pay agencies.

The rules on each side of the river

Missouri. Missouri's Professional Employer Organization Act (2018) requires PEOs to register with the Secretary of State, which keeps a list of registered PEOs (RSMo 285.715). The Act excludes temporary help services from what counts as a PEO (RSMo 285.705), so temp agencies don't register under it. Check a temp or placement agency's business entity record with the Secretary of State, its workers' compensation certificate and its references.

Illinois (Madison, St. Clair and other Metro East counties). The Illinois Day and Temporary Labor Services Act requires covered agencies to register with the Illinois Department of Labor (IDOL) before operating in the state. Registration costs $3,000 a year per agency plus $750 per branch, with proof of a surety bond. Agencies that staff only clerical or professional workers may be exempt. Clients must verify registration before contracting and again every March 1 and September 1.

What that means in practice:

• IDOL's registered agencies list (as of 1 October 2026) has 19 records with addresses in Madison and St. Clair counties, in Edwardsville, Granite City, Collinsville, Glen Carbon, Maryville, Fairview Heights and Swansea.
• Eight records on the same list have Missouri addresses (St. Louis, Chesterfield and Earth City), so some Missouri-based agencies are registered to work across the river.
• Before a Missouri agency sends industrial temps to your Illinois plant, find its name on the list and keep a dated copy.

Worked example: contingency or retained search?

Illustrative example. The company, salary and fee rates are invented to show the arithmetic; fee rates vary by firm.

Gateway Ridge Foods (gatewayridge.example) needs a VP of operations at a $180,000 base salary with a 20% target bonus, $216,000 in first-year cash. Two St. Louis search firms quote:

The retained search costs $19,800 more when it succeeds and $43,200 when it doesn't. It earns that premium when the role is confidential, senior or hard to fill; for a role with a deep local pool, contingency firms competing for the fee may fill it faster. Either way, ask for the guarantee period and whether the fee is refunded or the search redone if the hire leaves early.

Selling to St. Louis staffing agencies

Two lists, two pitches. For the 49 one- and two-person search firms, sell tools that save a recruiter hours (research, sourcing, reference checks), and expect the owner to decide in one call. For temp branches, start with the 19 Metro East registry records and the 95 St. Louis agencies on ClearlyRated, then read job posts to find the branches staffing warehouses in St. Charles County or plants in Madison County. Illinois-registered agencies also carry compliance work Missouri ones don't, so registry-related services fit them better. At volume, account research is the slow part; Bebop finds agencies that match a description and explains why each fits. For outreach, see how to write a cold email.

Subject: Finalist references for [firm]'s next search

Hi [first name],

I saw [firm] is running a search for [role] in St. Louis. At a firm your size, reference calls on finalists usually land on you, in the same week as the client presentation.

We [what you do, e.g. run structured reference calls and send a written summary within 48 hours], billed per finalist.

Worth trying on your next shortlist?

[Your name]

Local sources

Next step: see how Illinois agencies statewide compare in staffing agencies in Illinois.