Company lists · Data refreshed September 2026

Top 25 Clinical research organizations based in the United States

Name: Clinical research organizations based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 16, 2026 3,508 companies tracked

RevenueBase identified 3,508 clinical research organizations headquartered in the United States as of September 2026 and tracks 285,159 professional contacts across them, including 125,836 with verified work emails. Miami is the largest hub.

This list covers clinical research organizations 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 16, 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 16, 2026 86% judged on-target in blind review

3,508Companies

285,159Contacts tracked

125,836Verified emails

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The 25 largest clinical research organizations based in the United States

Ranked by team size

Top 25 of 3,508 clinical research organizations based in the United States, ranked by team size, largest first. Data refreshed Sep 16, 2026. RevenueBase Smart Search rates how each company's information relates to clinical research organizations: 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	IQVIA	Strong evidence	Durham, NC, United StatesHQ checked Sep 16, 2026	10001+	63,824 contacts →
	Strong evidence “IQVIA (NYSE:IQV) is a leading global provider of clinical research services, commercial insights and healthcare intelligence to the life sciences and healthcare industries.” Source: RevenueBase Database · checked Sep 16, 2026
2	PPD	Strong evidence	Waltham, MA, United StatesHQ checked Sep 16, 2026	10001+	20,530 contacts →
	Strong 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 16, 2026
3	Parexel	Strong evidence	Raleigh, NC, United StatesHQ checked Sep 16, 2026	10001+	19,257 contacts →
	Strong evidence “Parexel is a leading global clinical research organization (CRO) providing insights-driven Clinical and Consulting solutions to the world’s life sciences industry.” Source: RevenueBase Database · checked Sep 16, 2026
4	Syneos Health	Indirect evidence	Morrisville, NC, United StatesHQ checked Sep 16, 2026	10001+	18,228 contacts →
	Indirect evidence “Syneos Health® is a leading fully integrated biopharmaceutical solutions organization built to accelerate customer success.” Source: RevenueBase Database · checked Sep 16, 2026
5	Fortrea	Strong evidence	Research Triangle Park, NC, United StatesHQ checked Sep 16, 2026	10001+	10,632 contacts →
	Strong evidence “Fortrea (Nasdaq: FTRE) is a leading global clinical research organization (CRO) dedicated to providing innovative clinical development solutions to the life sciences industry.” Source: RevenueBase Database · checked Sep 16, 2026
6	Medpace	Strong evidence	Cincinnati, OH, United StatesHQ checked Sep 16, 2026	5,001-10,000	5,960 contacts →
	Strong evidence “Medpace is a scientifically-driven, global, full-service clinical contract research organization (CRO) providing Phase I-IV clinical development services to the biotechnology…” Source: RevenueBase Database · checked Sep 16, 2026
7	Covance	Indirect evidence	Princeton, NJ, United StatesHQ checked Sep 16, 2026	10001+	5,220 contacts →
	Indirect evidence “As the drug development business of Laboratory Corporation of America Holdings (Labcorp) and the world’s most comprehensive drug development #CRO service company, we have helped…” Source: RevenueBase Database · checked Sep 16, 2026
8	PRA Health Sciences	Indirect evidence	Raleigh, NC, United StatesHQ checked Sep 16, 2026	10001+	4,708 contacts →
	Indirect evidence “PRA is now an ICON plc company.” Source: RevenueBase Database · checked Sep 16, 2026
9	Worldwide Clinical Trials	Partial evidence	Research Triangle Park, NC, United StatesHQ checked Sep 16, 2026	1,001-5,000	3,440 contacts →
	Partial evidence “Worldwide Clinical Trials (Worldwide) is a global CRO serving development-driven biopharmaceutical companies, with more than 4,400 professionals operating across more than 70…” Source: RevenueBase Database · checked Sep 16, 2026
10	Westat	Indirect evidence	Bethesda, MD, United StatesHQ checked Sep 16, 2026	1,001-5,000	3,248 contacts →
	Indirect evidence “Westat offers innovative professional services to help clients improve outcomes in health, education, and social policy.” Source: RevenueBase Database · checked Sep 16, 2026
11	Eversana	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 16, 2026	5,001-10,000	3,149 contacts →
	Indirect evidence “EVERSANA® is a leading independent provider of global services to the life sciences industry.” Source: RevenueBase Database · checked Sep 16, 2026
12	Medidata Solutions	Partial evidence	New York, NY, United StatesHQ checked Sep 16, 2026	1,001-5,000	2,704 contacts →
	Partial evidence “Medidata is powering smarter treatments and healthier people through digital solutions to support clinical trials.” Source: RevenueBase Database · checked Sep 16, 2026
13	Premier Research	Strong evidence	Morrisville, NC, United StatesHQ checked Sep 16, 2026	1,001-5,000	2,584 contacts →
	Strong evidence “Premier Research International LLC (Premier) is a global leader in clinical research and consulting services with expertise in driving an efficient and effective path to market…” Source: RevenueBase Database · checked Sep 16, 2026
14	Signant Health	Strong evidence	Blue Bell, PA, United StatesHQ checked Sep 16, 2026	1,001-5,000	2,083 contacts →
	Strong evidence “For 25+ years, Signant Health has been pioneering solutions and methodologies that propel clinical research programs toward regulatory success.” Source: RevenueBase Database · checked Sep 16, 2026
15	Propharma	Indirect evidence	Raleigh, NC, United StatesHQ checked Sep 16, 2026	1,001-5,000	2,079 contacts →
	Indirect evidence “At ProPharma, we help pharmaceutical, biotechnology, and medical device companies bring life-changing therapies to market.” Source: RevenueBase Database · checked Sep 16, 2026
16	Patheon	Partial evidence	Waltham, MA, United StatesHQ checked Sep 16, 2026	10001+	2,004 contacts →
	Partial evidence “Thermo Fisher Scientific provides industry-leading pharma services for drug development, clinical trial logistics, and commercial manufacturing through our Patheon™ brand.” Source: RevenueBase Database · checked Sep 16, 2026
17	UBC	Indirect evidence	King Of Prussia, PA, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,858 contacts →
	Indirect evidence “United BioSource LLC (UBC) is the leading provider of evidence development solutions with expertise in uniting evidence and access.” Source: RevenueBase Database · checked Sep 16, 2026
18	Precision For Medicine	Strong evidence	Bethesda, MD, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,781 contacts →
	Strong evidence “Precision for Medicine is an industry-leading global clinical research services organization, purpose-built to improve the clinical research and development process for new…” Source: RevenueBase Database · checked Sep 16, 2026
19	Advarra	Partial evidence	Columbia, MD, United StatesHQ checked Sep 16, 2026	501-1,000	1,581 contacts →
	Partial evidence “Advarra provides the platform, insights, and expertise that make clinical trials more efficient and connected.” Source: RevenueBase Database · checked Sep 16, 2026
20	CYTEL	Partial evidence	Cambridge, MA, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,580 contacts →
	Partial evidence “Cytel is the world’s leading data-science CRO, driving advancements in human health through robust analytics and innovative clinical trial software.” Source: RevenueBase Database · checked Sep 16, 2026
21	Clinchoice	Indirect evidence	Horsham, PA, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,516 contacts →
	Indirect evidence “ClinChoice is a leading global full & functional service CRO, renowned for its exceptional product development and lifecycle management capabilities across the pharmaceutical…” Source: RevenueBase Database · checked Sep 16, 2026
22	NAMSA	Partial evidence	Toledo, OH, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,275 contacts →
	Partial evidence “Helping medical device Sponsors improve healthcare since 1967, NAMSA is the world’s leading MedTech Contract Research Organization (CRO) offering global end-to-end development…” Source: RevenueBase Database · checked Sep 16, 2026
23	Suvoda	Partial evidence	Conshohocken, PA, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,255 contacts →
	Partial evidence “Suvoda is a global clinical trial technology company, now strengthened by our merger with Greenphire.” Source: RevenueBase Database · checked Sep 16, 2026
24	ERT	Partial evidence	Philadelphia, PA, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,255 contacts →
	Partial evidence “ERT, the global clinical endpoint technology leader, and Bioclinica, a technological and scientific leader in medical imaging, is now the combined company of Clario.” Source: RevenueBase Database · checked Sep 16, 2026
25	WCG	Strong evidence	Cary, NC, United StatesHQ checked Sep 16, 2026	1,001-5,000	1,103 contacts →
	Strong evidence “WCG is a true partner to research sponsors, CROs, sites and participants in navigating the clinical research journey.” Source: RevenueBase Database · checked Sep 16, 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: clinical research organizations. 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 clinical research organizations.
Partial evidence: Its own public description names part of clinical research organizations, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name clinical research organizations. 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 3,508 clinical research organizations based in the United States

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Clinical research organizations based in the United States at a glance

As of Sep 16, 2026

44.1%Verified-email coverage

81.3Average contacts per company

11-50Median size (employees)

2.6%Largest-city concentration · Miami

Sep 16, 2026Page data refreshed

Companies by employee count

1-10

1,533

11-50

1,227

51-200

451

201-500

132

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 3,508 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 clinical research organizations, 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 “clinical research organizations”. 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 clinical research organizations), 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 clinical research organizations, 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, 125,836 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 16, 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.

Clinical research organizations 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 clinical research organizations, 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 clinical research organizations are there based in the United States?

RevenueBase identified 3,508 clinical research organizations 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?

IQVIA, headquartered in Durham, tops this list with the largest team on record.

Which city has the most clinical research organizations?

Miami leads with 91 headquartered companies, followed by New York (84) and San Diego (84).

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 125,836 verified decision-maker contacts tracked across these 3,508 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 16, 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.