Company lists · Data refreshed September 2026

Top 25 HR outsourcing firms based in the United States

Name: HR outsourcing firms based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 30, 2026 9,913 companies tracked

RevenueBase identified 9,913 company matches for HR outsourcing firms associated with the United States as of September 2026 and tracks 330,010 professional contacts across them, including 93,606 with verified work emails and 94,047 with mobile numbers. New York is the largest hub.

This list covers company matches for HR outsourcing firms associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed September 30, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, 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 RevenueBase SmartSearch · Exact Recorded Sep 30, 2026 How this list was built

9,913Companies

330,010Contacts tracked

93,606Verified emails

94,047Mobile numbers

Explore this list → Free signup · no credit card · 500 free credits

The 25 largest HR outsourcing firms based in the United States

Ranked by team size

Top 25 of 9,913 company matches for HR outsourcing firms based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 30, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	ADP	Exact match	Roseland, NJ, United StatesHQ recorded Sep 30, 2026	10001+	84,166 contacts →
	Exact match “Designing better ways to work through cutting-edge products, premium services and exceptional experiences that enable people to reach their full potential.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
2	Paychex	Exact match	Rochester, NY, United StatesHQ recorded Sep 30, 2026	10001+	17,911 contacts →
	Exact match “As the future of work continues to evolve, Paychex leads the way by making complex HR, payroll, and benefits brilliantly simple.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
3	Insight Global	Exact match	Atlanta, GA, United StatesHQ recorded Sep 30, 2026	n/a	15,553 contacts →
	Exact match “Insight Global is an international talent and consulting company that delivers business outcomes in an ever-changing world.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
4	LHH	Exact match	Jacksonville, FL, United StatesHQ recorded Sep 30, 2026	10001+	12,889 contacts →
	Exact match “At LHH, we believe work should be meaningful, fulfilling, and connected.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
5	Express Employment International	Exact match	Oklahoma City, OK, United StatesHQ recorded Sep 30, 2026	10001+	12,647 contacts →
	Exact match “Founded in 1983 and corporately headquartered in Oklahoma City, Express Employment International supports the Express Employment Professionals franchise and related brands.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
6	Randstad USA	Exact match	Atlanta, GA, United StatesHQ recorded Sep 30, 2026	1,001-5,000	8,522 contacts →
	Exact match “Randstad North America, Inc.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
7	Strada	Exact match	The Woodlands, TX, United StatesHQ recorded Sep 30, 2026	5,001-10,000	5,585 contacts →
	Exact match “With over 30 years as a global people, payroll, and technology leader, Strada specializes in removing complexity to simplify workforce management.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
8	Insperity	Exact match	Kingwood, TX, United StatesHQ recorded Sep 30, 2026	1,001-5,000	4,761 contacts →
	Exact match “Since 1986, Insperity’s mission has been to help businesses succeed so communities prosper.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
9	Trinet	Exact match	Dublin, CA, United StatesHQ recorded Sep 30, 2026	1,001-5,000	4,056 contacts →
	Exact match “TriNet (NYSE: TNET) provides small and medium-size businesses (SMBs) with full-service HR solutions tailored by industry.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
10	PSG Global Solutions	Exact match	Marina Del Rey, CA, United StatesHQ recorded Sep 30, 2026	1,001-5,000	4,000 contacts →
	Exact match “PSG is a global leader in recruitment process optimization, delivering high-performance outsourced recruiting solutions that drive real business results.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
11	GUSTO	Exact match	San Francisco, CA, United StatesHQ recorded Sep 30, 2026	1,001-5,000	3,543 contacts →
	Exact match “Gusto has been growing the small business economy for 15+ years.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
12	Allegis Global Solutions	Exact match	Hanover, MD, United StatesHQ recorded Sep 30, 2026	1,001-5,000	2,866 contacts →
	Exact match “At Allegis Global Solutions (AGS), we’re in the human enterprise business.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
13	Aston Carter	Exact match	Hanover, MD, United StatesHQ recorded Sep 30, 2026	1,001-5,000	2,437 contacts →
	Exact match “Aston Carter provides world-class corporate talent solutions to thousands of clients across the globe.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
14	Mindlance	Exact match	Union, NJ, United StatesHQ recorded Sep 30, 2026	1,001-5,000	2,096 contacts →
	Exact match “Mindlance is a global Talent, Teams, Projects, and Workforce Solutions partner, serving leading enterprises across industries since With a strong footprint across multiple…” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
15	Remedy Intelligent Staffing	Exact match	Atlanta, GA, United StatesHQ recorded Sep 30, 2026	10001+	1,948 contacts →
	Exact match “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…” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
16	Kronos Incorporated	Exact match	Lowell, MA, United StatesHQ recorded Sep 30, 2026	5,001-10,000	1,889 contacts →
	Exact match “Built from the merger of Ultimate Software & Kronos Inc, we are now UKG.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
17	Bamboohr	Exact match	Draper, UT, United StatesHQ recorded Sep 30, 2026	1,001-5,000	1,812 contacts →
	Exact match “For 16 years, BambooHR has embarked on a mission to help organizations and their employees build better workplaces and achieve their unique missions.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
18	Office Beacon LLC	Exact match	Redondo Beach, CA, United StatesHQ recorded Sep 30, 2026	5,001-10,000	1,409 contacts →
	Exact match “For 25 years, Office Beacon has helped companies scale smarter by providing fully managed remote staffing across every department, in every major industry.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
19	SEBPO	Exact match	Marlton, NJ, United StatesHQ recorded Sep 30, 2026	1,001-5,000	1,237 contacts →
	Exact match “SEBPO transforms operational complexity into a seamless, strategic advantage.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
20	Ultimate Staffing	Exact match	Orange, CA, United StatesHQ recorded Sep 30, 2026	501-1,000	1,196 contacts →
	Exact match “Meet Ultimate Staffing: Ultimate Staffing Services, a business line of Roth Staffing Companies, specializes in delivering temporary, temporary-to-hire, and direct hire services…” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
21	Peoplescout	Exact match	Chicago, IL, United StatesHQ recorded Sep 30, 2026	1,001-5,000	1,173 contacts →
	Exact match “PeopleScout, a TrueBlue company, is a global talent solutions leader.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
22	W3global	Exact match	Frisco, TX, United StatesHQ recorded Sep 30, 2026	501-1,000	1,149 contacts →
	Exact match “W3Global is a leading provider of end-to-end consulting services, empowering businesses to achieve their strategic goals and optimize their operations.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
23	247hire	Exact match	Oak Brook, IL, United StatesHQ recorded Sep 30, 2026	201-500	1,059 contacts →
	Exact match “At 247Hire, our mission is simple: to empower yours.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
24	Eclaro	Exact match	New York, NY, United StatesHQ recorded Sep 30, 2026	1,001-5,000	1,024 contacts →
	Exact match “ECLARO is an award-winning Talent Solutions firm headquartered in New York City and operating in the U.S, Canada and the Philippines.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
25	Intellipro	Exact match	San Jose, CA, United StatesHQ recorded Sep 30, 2026	501-1,000	990 contacts →
	Exact match “IntelliPro Group Inc.” Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “HR outsourcing firms”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 25 of 9,913 HR outsourcing firms based in the United States

See the full list, filter by size, metro and specialty, and access 93,606 tracked professional contacts with verified work emails. Direct dials are available where recorded.

Free signup · no credit card

View the full list →

HR outsourcing firms based in the United States at a glance

As of Sep 30, 2026

28.4%Verified-email coverage

28.5%Mobile-number coverage

33.3Average contacts per company

1-10Median size (employees)

4.2%Largest-city concentration · New York

Sep 30, 2026Page data refreshed

Companies by employee count

1-10

6,219

11-50

2,274

51-200

874

201-500

248

501-1,000

117

1,001-5,000

120

5,001-10,000

10001+

Freshness & accuracy

How recently the business emails were verified and the company information checked

Email last verified

Median 32.0d

27,4120–30

61,90831–60

3,18061–90

10490–180

1,002180+

Company record updated

Median 93.0d

00–30

45,99231–60

91,44461–90

169,90690–180

22,668180+

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies: Company records associated with the United States whose business descriptions match “HR outsourcing firms” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch: Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview: The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality: RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
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 displayed company carries at least one verified work email. RevenueBase tracks 93,606 professional contacts with verified work emails across the full matched dataset. 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 30, 2026. Lists refresh periodically as the graph is re-checked.
Record context: Company records and descriptions can change. Check the company's website for its current services and locations.

HR outsourcing firms by metro

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “HR outsourcing firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many HR outsourcing firms are there based in the United States?

RevenueBase identified 9,913 company matches for HR outsourcing firms associated with the United States as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

ADP tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most HR outsourcing firms?

New York leads with 417 company records, followed by Atlanta (236) and Houston (217).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 93,606 professional contacts with verified work emails tracked across these 9,913 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 30, 2026.

Ready to reach these companies? Verified emails and direct dials for all 9,913 HR outsourcing firms based in the United States. Start with a free account, no credit card.

Download this list →

Related lists

HR outsourcing firms by geography

Browse the directory

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 SmartSearch, 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.