Company lists · Data refreshed September 2026

Top 25 Cleanroom staffing agencies based in the United States

Name: Cleanroom staffing agencies based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 27, 2026 4,966 companies tracked

RevenueBase identified 4,966 cleanroom staffing agencies headquartered in the United States as of September 2026 and tracks 157,579 professional contacts across them, including 22,120 with verified work emails. Houston is the largest hub.

This list covers cleanroom staffing agencies headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 27, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 27, 2026 86% judged on-target in blind review

4,966Companies

157,579Contacts tracked

22,120Verified emails

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The 25 largest cleanroom staffing agencies based in the United States

Ranked by team size

Top 25 of 4,966 cleanroom staffing agencies based in the United States, ranked by team size, largest first. Data refreshed Sep 27, 2026. RevenueBase Smart Search rates how each company's information relates to cleanroom staffing agencies: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Appleone Employment Services	Indirect evidence	Glendale, CA, United StatesHQ checked Sep 27, 2026	1,001-5,000	4,627 contacts →
	Indirect evidence “AppleOne Employment Services is a full-service employment company.” Source: RevenueBase Database · checked Sep 27, 2026
2	Spherion	Partial evidence	Atlanta, GA, United StatesHQ checked Sep 27, 2026	10001+	4,263 contacts →
	Partial evidence “We’re Spherion-a staffing and recruiting pioneer that’s been driving careers and helping businesses grow for over 75 years.” Source: RevenueBase Database · checked Sep 27, 2026
3	Select Staffing	Partial evidence	Atlanta, GA, United StatesHQ checked Sep 27, 2026	10001+	3,934 contacts →
	Partial evidence “Select Staffing is a leading provider of temporary staffing and employment services in the U.S, with nationwide operations across multiple contingent staffing sectors.” Source: RevenueBase Database · checked Sep 27, 2026
4	Remedy Intelligent Staffing	Partial evidence	Atlanta, GA, United StatesHQ checked Sep 27, 2026	10001+	1,948 contacts →
	Partial evidence “Remedy Intelligent Staffing is a nationwide professional staffing organization with more than 50 years of recruiting and selection expertise to match job candidates with positions…” Source: RevenueBase Database · checked Sep 27, 2026
5	Labormax Staffing	Partial evidence	Kearney, MO, United StatesHQ checked Sep 27, 2026	n/a	1,755 contacts →
	Partial evidence “LaborMAX Staffing is your reliable provider of quality pre-screened contingent workers.” Source: RevenueBase Database · checked Sep 27, 2026
6	MEDIX	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 27, 2026	501-1,000	1,753 contacts →
	Indirect evidence “Medix provides workforce solutions to clients and creates opportunity for talent in the Healthcare, Life Sciences, Engineering and Technology fields.” Source: RevenueBase Database · checked Sep 27, 2026
7	Resourcemfg	Indirect evidence	Atlanta, GA, United StatesHQ checked Sep 27, 2026	5,001-10,000	1,639 contacts →
	Indirect evidence “ResourceMFG places temporary and direct hire employees within the total spectrum of manufacturing jobs including production, quality, maintenance, supervision, and all levels of…” Source: RevenueBase Database · checked Sep 27, 2026
8	Onin Staffing	Partial evidence	Birmingham, AL, United StatesHQ checked Sep 27, 2026	10001+	1,614 contacts →
	Partial evidence “Ōnin Staffing, a company of The Ōnin Group, is a national light industrial and clerical staffing agency.” Source: RevenueBase Database · checked Sep 27, 2026
9	Nesco Resource	Indirect evidence	Mayfield Heights, OH, United StatesHQ checked Sep 27, 2026	501-1,000	1,599 contacts →
	Indirect evidence “Companies need talent.” Source: RevenueBase Database · checked Sep 27, 2026
10	Infotree Global Solutions	Indirect evidence	Plymouth, MI, United StatesHQ checked Sep 27, 2026	1,001-5,000	1,545 contacts →
	Indirect evidence “Infotree Global was founded in 2002 in a small office in Canton, MI, Infotree Global had a clear mission; To bring the world’s best talent together with the greatest companies…” Source: RevenueBase Database · checked Sep 27, 2026
11	SELF	Indirect evidence	Houston, TX, United StatesHQ checked Sep 27, 2026	n/a	1,431 contacts →
	Indirect evidence “We are a Full Service Solutions Company specializing in placements of professionals in Information Technology, Finance/Accounting, Energy (front, mid and back office)…” Source: RevenueBase Database · checked Sep 27, 2026
12	Coworx Staffing Services	Partial evidence	Morristown, NJ, United StatesHQ checked Sep 27, 2026	201-500	1,286 contacts →
	Partial evidence “CoWorx Staffing Services is one of the largest staffing firms in the U.S.” Source: RevenueBase Database · checked Sep 27, 2026
13	Ultimate Staffing	Partial evidence	Orange, CA, United StatesHQ checked Sep 27, 2026	501-1,000	1,196 contacts →
	Partial evidence “Meet Ultimate Staffing: Ultimate Staffing Services, a business line of Roth Staffing Companies, specializes in delivering temporary, temporary-to-hire, and direct hire services…” Source: RevenueBase Database · checked Sep 27, 2026
14	TRS Staffing Solutions	Partial evidence	Greenville, United StatesHQ checked Sep 27, 2026	201-500	1,187 contacts →
	Partial evidence “TRS Staffing Solutions is a world leading engineering recruitment agency specialising in the recruitment and supply of professional, engineering, technical and field talent.” Source: RevenueBase Database · checked Sep 27, 2026
15	Planet Pharma	Partial evidence	Raleigh, NC, United StatesHQ checked Sep 27, 2026	1,001-5,000	1,088 contacts →
	Partial evidence “Founded in 2012, Planet Pharma is a global leader in life sciences recruitment and staffing, specializing in Pharmaceuticals, Biotechnology, Medical Device, Labs & Healthcare…” Source: RevenueBase Database · checked Sep 27, 2026
16	247hire	Indirect evidence	Oak Brook, IL, United StatesHQ checked Sep 27, 2026	201-500	1,059 contacts →
	Indirect evidence “At 247Hire, our mission is simple: to empower yours.” Source: RevenueBase Database · checked Sep 27, 2026
17	QPS Employment Group	Partial evidence	Brookfield, WI, United StatesHQ checked Sep 27, 2026	201-500	1,019 contacts →
	Partial evidence “Founded in 1985, QPS Employment Group has grown from a two-person operation to one of the nation's leading staffing and recruiting firms, with more than 300 internal employees…” Source: RevenueBase Database · checked Sep 27, 2026
18	Lyneer Staffing Solutions	Partial evidence	Ewing, NJ, United StatesHQ checked Sep 27, 2026	201-500	1,012 contacts →
	Partial evidence “The Solution to Your Staffing Needs Lyneer Staffing Solutions is a national workforce solutions company with over 25 years of experience in the staffing industry.” Source: RevenueBase Database · checked Sep 27, 2026
19	Hire Dynamics	Indirect evidence	Duluth, GA, United StatesHQ checked Sep 27, 2026	201-500	1,002 contacts →
	Indirect evidence “Opportunities.” Source: RevenueBase Database · checked Sep 27, 2026
20	Career Strategies	Partial evidence	Round Rock, TX, United StatesHQ checked Sep 27, 2026	n/a	955 contacts →
	Partial evidence “Career Strategies is a full service staffing firm specializing in Property Management, Healthcare and Professional Services recruitment.” Source: RevenueBase Database · checked Sep 27, 2026
21	Remx The Workforce Experts	Partial evidence	Atlanta, GA, United StatesHQ checked Sep 27, 2026	1,001-5,000	901 contacts →
	Partial evidence “RemX is the professional staffing division of EmployBridge, a $3 billion staffing organization with more than 600 offices in the U.S.” Source: RevenueBase Database · checked Sep 27, 2026
22	Imcs Group	Partial evidence	Irving, TX, United StatesHQ checked Sep 27, 2026	201-500	881 contacts →
	Partial evidence “IMCS Group is an IT, Healthcare, and Professional Staffing Company that helps Enterprises optimize the business value of their Staffing investments and enables them to achieve…” Source: RevenueBase Database · checked Sep 27, 2026
23	The Reserves Network	Partial evidence	Fairview Park, OH, United StatesHQ checked Sep 27, 2026	n/a	812 contacts →
	Partial evidence “The Reserves Network is a leading provider of staffing services for the Office, Industrial, Professional and Technical markets.” Source: RevenueBase Database · checked Sep 27, 2026
24	Integrated Resources, INC IRI	Partial evidence	Edison, NJ, United StatesHQ checked Sep 27, 2026	501-1,000	762 contacts →
	Partial evidence “Integrated Resources Inc.(IRI) is a professional staffing firm specializing in contract, consulting & full time positions in the area of Information Technology, Life Science and…” Source: RevenueBase Database · checked Sep 27, 2026
25	JSG Johnson Service Group, INC	Partial evidence	Westmont, IL, United StatesHQ checked Sep 27, 2026	5,001-10,000	757 contacts →
	Partial evidence “Johnson Service Group, Inc.(JSG) is a leader in the staffing and consulting services industry, with 40 years of experience investing in people and companies.” Source: RevenueBase Database · checked Sep 27, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: cleanroom staffing agencies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names cleanroom staffing agencies.
Partial evidence: Its own public description names part of cleanroom staffing agencies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name cleanroom staffing agencies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 4,966 cleanroom staffing agencies based in the United States

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Cleanroom staffing agencies based in the United States at a glance

As of Sep 27, 2026

14.0%Verified-email coverage

31.7Average contacts per company

11-50Median size (employees)

2.8%Largest-city concentration · Houston

Sep 27, 2026Page data refreshed

Companies by employee count

1-10

1,866

11-50

1,464

51-200

965

201-500

378

501-1,000

141

1,001-5,000

107

5,001-10,000

10001+

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 4,966 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among cleanroom staffing agencies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies: Companies headquartered in the United States whose own description of what they do matches “cleanroom staffing agencies”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names cleanroom staffing agencies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among cleanroom staffing agencies, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every listed company carries at least one verified work email, 22,120 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on September 27, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Cleanroom staffing agencies by metro

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names cleanroom staffing agencies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many cleanroom staffing agencies are there based in the United States?

RevenueBase identified 4,966 cleanroom staffing agencies headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Appleone Employment Services, headquartered in Glendale, tops this list with the largest team on record.

Which city has the most cleanroom staffing agencies?

Houston leads with 141 headquartered companies, followed by New York (129) and Dallas (91).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 22,120 verified decision-maker contacts tracked across these 4,966 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 27, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.