Company lists · Data refreshed September 2026
Top 25 Healthy volunteer recruitment firms based in the United States
RevenueBase identified 1,222 healthy volunteer recruitment firms headquartered in the United States as of September 2026 and tracks 45,615 professional contacts across them, including 16,447 with verified work emails. Miami is the largest hub.
This list covers healthy volunteer recruitment firms 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 28, 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.
The 25 largest healthy volunteer recruitment firms based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 20,530 contacts → | ||||
Indirect evidence “The PPD™ clinical research business of Thermo Fisher Scientific, the world leader in serving science, enables customers to accelerate innovation and drug development through…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 2 | 1,538 contacts → | ||||
Indirect evidence “In recruiting, stating actual facts has become: Foreign | Uncommon | Taboo.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 3 | 971 contacts → | ||||
Indirect evidence “Velocity is the world’s leading organization of fully integrated clinical research sites.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 4 | 847 contacts → | ||||
Indirect evidence “CenExel is a leading integrated, wholly owned, nationwide clinical research site network comprised of 18 Centers of Excellence in major metropolitan areas across the U.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 5 | 770 contacts → | ||||
Strong evidence “MMG is a full-service global health communications group that specializes in patient recruitment and retention.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 6 | 590 contacts → | ||||
Indirect evidence “DM Clinical Research is a network of clinical trial investigator sites with headquarters based out of Houston, Texas.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 7 | 561 contacts → | ||||
Indirect evidence “Accelerated Enrollment Solutions (AES) is now Trialmed.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 8 | 528 contacts → | ||||
Indirect evidence “While the availability of medical technicians and professionals becomes increasingly limited, there seems to be no shortage of staffing firms.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 9 | 481 contacts → | ||||
Strong evidence “HealthCare Support is a national niche recruitment firm that has a singular focus - placing top talent in the dynamic healthcare industry.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 10 | 458 contacts → | ||||
Strong evidence “Avant Healthcare Professionals is a leader in international healthcare recruitment and staffing, connecting globally educated nurses and allied health professionals with hospitals…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 11 | 334 contacts → | ||||
Indirect evidence “Talent4Health is the most candidate-centric agency in the industry.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 12 | 321 contacts → | ||||
Indirect evidence “Flourish Research is a fully integrated, multi-site clinical trial network serving sponsors and CROs across North America.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 13 | 291 contacts → | ||||
Indirect evidence “Science 37 is a modern clinical research site that delivers trials directly to patients’ homes.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 14 | 260 contacts → | ||||
Indirect evidence “PCM Trials acquired EmVenio Research and Netherlands-based Clinical Trials Service in 2024.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 15 | 254 contacts → | ||||
Partial evidence “Elligo Health Research is an integrated research organization founded to bridge the gap between cutting-edge clinical trials and the patients who need them-an idea that sparked…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 16 | 229 contacts → | ||||
Indirect evidence “Since 2005, KlinEra has partnered with some of the largest pharmaceutical, biotech and device companies, providing innovative and customized clinical trial and research services.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 17 | 226 contacts → | ||||
Indirect evidence “Welcome to K2 Medical Research, a privately-owned clinical research facility with multiple locations in Florida, Tennessee, and Rhode Island.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 18 | 207 contacts → | ||||
Partial evidence “Luke & Associates (Luke) is a trusted provider of healthcare and professional services.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 19 | 201 contacts → | ||||
Indirect evidence “EmVenio Clinical Research, a Professional Case Management subsidiary, operates from U.S.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 20 | 200 contacts → | ||||
Indirect evidence “K.A.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 21 | 172 contacts → | ||||
Partial evidence “Aequor Healthcare Services is a US-based healthcare personnel provider that specializes in staffing physicians, therapists, nurses, technologist and aides.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 22 | 171 contacts → | ||||
Indirect evidence “Clinical Trial Media (CTM) is the largest full-service global patient enrollment organization, with three decades of experience supporting pharmaceutical and biotechnology…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 23 | 167 contacts → | ||||
Partial evidence “Established in 2001, The Medicus Firm (TMF) is a national retained healthcare search firm with a mission to save lives through teamwork and the relentless pursuit of excellence.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 24 | 161 contacts → | ||||
Indirect evidence “M3 Wake Research is a premier clinical trial network that has been conducting studies since 1984.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 25 | 159 contacts → | ||||
Partial evidence “WorldWide HealthStaff Solutions Ltd.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
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: healthy volunteer recruitment firms. 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 healthy volunteer recruitment firms.
- Partial evidence
- Its own public description names part of healthy volunteer recruitment firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name healthy volunteer recruitment firms. 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 1,222 healthy volunteer recruitment firms based in the United States
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Healthy volunteer recruitment firms based in the United States at a glance
As of Sep 28, 2026Companies by employee count
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 1,222 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 healthy volunteer recruitment firms, 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 “healthy volunteer recruitment firms”. 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 healthy volunteer recruitment firms), 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 healthy volunteer recruitment firms, 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, 16,447 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 28, 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.
Healthy volunteer recruitment firms 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 healthy volunteer recruitment firms, 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 healthy volunteer recruitment firms are there based in the United States?
RevenueBase identified 1,222 healthy volunteer recruitment firms 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?
PPD, headquartered in Waltham, tops this list with the largest team on record.
Which city has the most healthy volunteer recruitment firms?
Miami leads with 41 headquartered companies, followed by Houston (30) and New York (30).
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 16,447 verified decision-maker contacts tracked across these 1,222 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 28, 2026.
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Healthy volunteer recruitment firms by geography
- Healthy volunteer recruitment firms based in Sydney, Australia
- Healthy volunteer recruitment firms based in Paris, France
- Healthy volunteer recruitment firms based in London, United Kingdom
- Healthy volunteer recruitment firms based in Atlanta, United States
- Healthy volunteer recruitment firms based in Houston, United States
- Healthy volunteer recruitment firms based in Miami, United States
- Healthy volunteer recruitment firms based in New York, United States
- Healthy volunteer recruitment firms based in Australia
- Healthy volunteer recruitment firms based in Canada
- Healthy volunteer recruitment firms based in France
- Healthy volunteer recruitment firms based in Germany
- Healthy volunteer recruitment firms based in India
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.
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- Healthy volunteer recruitment firms based in Sydney, Australia
- Healthy volunteer recruitment firms based in Paris, France
- Healthy volunteer recruitment firms based in London, United Kingdom
- Healthy volunteer recruitment firms based in Atlanta, United States
- Healthy volunteer recruitment firms based in Houston, United States
- Healthy volunteer recruitment firms based in Miami, United States