Company lists · Data refreshed November 2026

Top 25 Human resources outsourcing services based in the United States

Name: Human resources outsourcing services based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Nov 5, 2026 5,163 companies tracked

RevenueBase identified 5,163 company matches for human resources outsourcing services associated with the United States as of November 2026 and tracks 126,091 professional contacts across them, including 43,117 with verified work emails. New York is the largest hub.

This list covers company matches for human resources outsourcing services 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 November 5, 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 Nov 5, 2026 How this list was built

5,163Companies

126,091Contacts tracked

43,117Verified emails

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The 25 largest human resources outsourcing services based in the United States

Ranked by team size

Top 25 of 5,163 company matches for human resources outsourcing services based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 5, 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	Paychex	Exact match	Rochester, NY, United StatesHQ recorded Nov 5, 2026	10001+	18,792 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 · Nov 5, 2026 · View company records in RevenueBase
2	LHH	Exact match	Jacksonville, TX, United StatesHQ recorded Nov 5, 2026	10001+	13,920 contacts →
	Exact match “At LHH, we believe work should be meaningful, fulfilling, and connected.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
3	Randstad USA	Exact match	Atlanta, GA, United StatesHQ recorded Nov 5, 2026	1,001-5,000	9,496 contacts →
	Exact match “Randstad North America, Inc.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
4	Insperity	Exact match	Kingwood, TX, United StatesHQ recorded Nov 5, 2026	1,001-5,000	4,943 contacts →
	Exact match “Since 1986, Insperity’s mission has been to help businesses succeed so communities prosper.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
5	Trinet	Exact match	Dublin, CA, United StatesHQ recorded Nov 5, 2026	1,001-5,000	4,432 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 · Nov 5, 2026 · View company records in RevenueBase
6	GUSTO	Exact match	San Francisco, CO, United StatesHQ recorded Nov 5, 2026	1,001-5,000	4,083 contacts →
	Exact match “Gusto has been growing the small business economy with technology and heart for more than a decade.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
7	Vensure Employer Solutions	Exact match	Chandler, FL, United StatesHQ recorded Nov 5, 2026	1,001-5,000	2,771 contacts →
	Exact match “VensureHR is the direct employer services business unit of Vensure Employer Solutions, the largest privately held organization in the HR technology and services sector, delivering…” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
8	BBSI	Exact match	Vancouver, WA, United StatesHQ recorded Nov 5, 2026	501-1,000	1,708 contacts →
	Exact match “We started as a staffing company in 1972, and over the past 50 years, evolved into a Professional Employer Organization or PEO.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
9	Justworks	Exact match	New York, NY, United StatesHQ recorded Nov 5, 2026	1,001-5,000	1,686 contacts →
	Exact match “Justworks takes the busyness out of growing a business and alleviates the unknown.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
10	G&a Partners	Exact match	Houston, CA, United StatesHQ recorded Nov 5, 2026	501-1,000	915 contacts →
	Exact match “Managing HR, payroll, benefits, and compliance can stretch your team thin, and mistakes are costly.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
11	OASIS	Exact match	West Palm Beach, FL, United StatesHQ recorded Nov 5, 2026	501-1,000	883 contacts →
	Exact match “Oasis, A Paychex Company, is a leading Professional Employer Organization (PEO).” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
12	Mineral, Part Of Mitratech	Exact match	Portland, OR, United StatesHQ recorded Nov 5, 2026	201-500	757 contacts →
	Exact match “Trusted by more than 1 million companies, Mineral is the HR and compliance leader for growing businesses.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
13	Group Management Services, INC	Exact match	Richfield, NC, United StatesHQ recorded Nov 5, 2026	501-1,000	611 contacts →
	Exact match “We provide comprehensive HR solutions to companies of all sizes throughout the United States.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
14	MMC Group LP	Exact match	Irving, TX, United StatesHQ recorded Nov 5, 2026	51-200	534 contacts →
	Exact match “For over 35 years, MMC has been a trusted leader in Staffing and Payroll solutions, serving the private, public, and federal sectors with unparalleled excellence.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
15	Coadvantage	Exact match	Bradenton, FL, United StatesHQ recorded Nov 5, 2026	201-500	519 contacts →
	Exact match “CoAdvantage is now CoAd.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
16	Infosync	Exact match	Wichita, KS, United StatesHQ recorded Nov 5, 2026	501-1,000	517 contacts →
	Exact match “In today's fast-paced business landscape, multi-unit companies demand more than just basic operations-they need expert guidance and cutting-edge technology to thrive.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
17	Anywhere	Exact match	Silicon Valley, CA, United StatesHQ recorded Nov 5, 2026	n/a	510 contacts →
	Exact match “Nós nascemos no Vale do Silício e aqui aprendemos técnicas inovadoras sobre como fazer Talent Acquisition de uma forma estratégica e que gere impacto no negócio, nós não só…” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
18	Prismhr	Exact match	Chandler, FL, United StatesHQ recorded Nov 5, 2026	201-500	481 contacts →
	Exact match “PrismHR creates exceptional software and services, empowering human resource outsourcing service providers such as Professional Employer Organizations (PEOs) and HR outsourcers to…” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
19	Vertex Group	Exact match	Olean, NY, United StatesHQ recorded Nov 5, 2026	501-1,000	449 contacts →
	Exact match “Vertex Global Services is one of the leading Business Optimization Solutions provider globally- Ranked 19th amongst 50 most innovative companies across the globe.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
20	Proservice Hawaii	Exact match	Honolulu, HI, United StatesHQ recorded Nov 5, 2026	201-500	433 contacts →
	Exact match “ProService Hawaii provides bundled HR solutions that make it easier for employers to succeed.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
21	HKA Enterprises	Exact match	Duncan, CO, United StatesHQ recorded Nov 5, 2026	1,001-5,000	431 contacts →
	Exact match “One of the most important aspects of any company is its people.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
22	Headway Workforce Solutions	Exact match	Raleigh, NC, United StatesHQ recorded Nov 5, 2026	n/a	414 contacts →
	Exact match “Headway Workforce Solutions is a leading B2B (Business to Business) provider of HR Administration Outsourcing and Talent Solutions.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
23	Engage PEO	Exact match	Fort Lauderdale, TX, United StatesHQ recorded Nov 5, 2026	501-1,000	412 contacts →
	Exact match “Engage PEO delivers comprehensive HR solutions to small and medium-sized businesses, sharpening their competitive advantage.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
24	Frankcrum	Exact match	Clearwater, FL, United StatesHQ recorded Nov 5, 2026	201-500	412 contacts →
	Exact match “FrankCrum offers outsourced HR, payroll and payroll administration, employee benefits and benefits administration, 401(k), workers compensation and HR Solutions.” Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
25	Nextep	Exact match	Norman, OK, United StatesHQ recorded Nov 5, 2026	201-500	394 contacts →
	Exact match “Most founders don't start a business because they love navigating HR compliance, filing payroll taxes, or negotiating healthcare premiums.” Recorded in the RevenueBase company graph · Nov 5, 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 “human resources outsourcing services”. 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 5,163 human resources outsourcing services based in the United States

See the full list, filter by size, metro and specialty, and access 43,117 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Human resources outsourcing services based in the United States at a glance

As of Nov 5, 2026

34.2%Verified-email coverage

24.4Average contacts per company

1-10Median size (employees)

2.9%Largest-city concentration · New York

Nov 5, 2026Page data refreshed

Companies by employee count

1-10

3,389

11-50

1,098

51-200

394

201-500

108

501-1,000

1,001-5,000

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 5,163 companies.

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 “human resources outsourcing services” 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 43,117 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 November 5, 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.

Human resources outsourcing services 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 “human resources outsourcing services”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many human resources outsourcing services are there based in the United States?

RevenueBase identified 5,163 company matches for human resources outsourcing services associated with the United States as of November 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?

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

Which city has the most human resources outsourcing services?

New York leads with 152 company records, followed by Atlanta (103) and Houston (97).

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 43,117 professional contacts with verified work emails tracked across these 5,163 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 November 5, 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 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.