Company lists · Data refreshed September 2026

Top 25 Investigation firms based in the United States

RevenueBase identified 4,013 company matches for investigation firms associated with the United States as of September 2026 and tracks 43,349 professional contacts across them, including 11,857 with verified work emails. New York is the largest hub.

This list covers company matches for investigation 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 20, 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 20, 2026 How this list was built
4,013Companies
43,349Contacts tracked
11,857Verified emails
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The 25 largest investigation firms based in the United States

Ranked by team size
Top 25 of 4,013 company matches for investigation firms based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 20, 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.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchRoswell, GA, United StatesHQ recorded Sep 20, 202610001+3,592 contacts →

Exact match

“U.S.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
2Exact matchVienna, VA, United StatesHQ recorded Sep 20, 20261,001-5,0001,230 contacts →

Exact match

“Cellebrite is the leader in digital intelligence and investigative analytics, partnering with public and private organizations to transform how they manage data in investigations…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
3Exact matchMemphis, TN, United StatesHQ recorded Sep 20, 2026501-1,000748 contacts →

Exact match

“EFI Global is a multidisciplinary consulting firm that helps clients investigate, assess and resolve complex property, infrastructure and financial challenges.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
4Exact matchHerndon, VA, United StatesHQ recorded Sep 20, 20261,001-5,000677 contacts →

Exact match

“OMNIPLEX World Services Corporation is a leader and innovator in delivering professional background investigations, intelligence support, and physical security services to…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
5Exact matchLos Angeles, CA, United StatesHQ recorded Sep 20, 20261,001-5,000626 contacts →

Exact match

“Professional Security Consultants, Inc.(PSC) is a world-class provider of security guard services, patrol, investigations, backgrounds, consulting, security screening & specialty…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
6Exact matchGrand Rapids, MI, United StatesHQ recorded Sep 20, 20261,001-5,000572 contacts →

Exact match

“DK Security is unique in that it offers a single company for a wide ranging availability of security and investigative services.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
7Exact matchJacksonville, FL, United StatesHQ recorded Sep 20, 2026501-1,000518 contacts →

Exact match

“CoventBridge Group is the leading worldwide full service investigation solutions company providing: Surveillance, SIU and Compliance, Claims Investigation, Counter-Fraud Programs…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
8Exact matchSan Juan, United StatesHQ recorded Sep 20, 20261,001-5,000511 contacts →

Exact match

“Founded in 1982, Ranger American is a professional security organization with an extensive background in the security and investigation fields.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
9Exact matchAurora, IL, United StatesHQ recorded Sep 20, 2026201-500480 contacts →

Exact match

“Engineering Systems Inc.(ESi) is a forensic engineering and scientific investigation firm committed to providing actionable solutions to industry and technical challenges through…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
10Exact matchSt. Paul, MN, United StatesHQ recorded Sep 20, 20261,001-5,000404 contacts →

Exact match

“American Security & Investigations has provided security and investigative services throughout the upper midwest since 1959.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
11Exact matchBoston, MA, United StatesHQ recorded Sep 20, 2026201-500383 contacts →

Exact match

“Founded in 1933, MDD is a leading international forensic accounting firm that provides economic damage quantification assessments for its clients.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
12Exact matchChicago, IL, United StatesHQ recorded Sep 20, 2026201-500376 contacts →

Exact match

“Envista Forensics is the global leader in providing comprehensive forensic consulting and engineering services.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
13Exact matchSt. Petersburg, FL, United StatesHQ recorded Sep 20, 20261,001-5,000373 contacts →

Exact match

“Ethos Risk Services is a technology-backed, full-service claims management company.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
14Exact matchAtlanta, GA, United StatesHQ recorded Sep 20, 2026501-1,000340 contacts →

Exact match

“A full-service firm with the proven capabilities to manage all facets of your company’s security requirements, Norred & Associates, Inc.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
15Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-500336 contacts →

Exact match

“Vcheck is a global investigations firm that helps institutions protect their investments by providing intelligence on individuals and entities.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
16Exact matchDavis, CA, United StatesHQ recorded Sep 20, 2026201-500327 contacts →

Exact match

“DigiStream Investigations is a full-service private investigation firm specializing in insurance defense and legal support services.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
17Exact matchColumbus, OH, United StatesHQ recorded Sep 20, 2026201-500297 contacts →

Exact match

“Established in 1970, S-E-A is a recognized worldwide leader in forensic analysis and investigation.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
18Exact matchBroussard, LA, United StatesHQ recorded Sep 20, 2026501-1,000292 contacts →

Exact match

“HUB Enterprises is a national insurance defense investigative firm.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
19Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-500268 contacts →

Exact match

“We stand at the forefront of leadership, insight, and guidance in a world marked by complexity and uncertainty.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
20Exact matchAlbuquerque, NM, United StatesHQ recorded Sep 20, 2026501-1,000252 contacts →

Exact match

“ADC supports government and corporate clients with two primary services - personnel security, ranging from pre-employment checks to comprehensive background investigations and…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
21Exact matchLos Angeles, CA, United StatesHQ recorded Sep 20, 2026201-500232 contacts →

Exact match

“Founded in 1998, Resolution Economics provides sophisticated economic, statistical, and financial analyses, forensic investigations, forensic technology, dispute advisory, expert…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
22Exact matchArlington, TX, United StatesHQ recorded Sep 20, 2026201-500230 contacts →

Exact match

“A national portfolio of premier forensic services companies, Aperture uses proven science and accepted industry standards to deliver accurate and efficient expert analysis.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
23Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-500216 contacts →

Exact match

“T&M USA provides seamlessly integrated executive protection, investigative and consulting services.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
24Exact matchIrvine, CA, United StatesHQ recorded Sep 20, 2026201-500214 contacts →

Exact match

“Frasco has hundreds of investigators and regional offices located throughout the country.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
25Exact matchKannapolis, NC, United StatesHQ recorded Sep 20, 2026201-500214 contacts →

Exact match

“Advantage Investigations is a nationwide leader in the industry for investigative services.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase

Showing 25 of 4,013 investigation firms based in the United States

See the full list, filter by size, metro and specialty, and access 11,857 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Investigation firms based in the United States at a glance

As of Sep 20, 2026
27.4%Verified-email coverage
10.8Average contacts per company
1-10Median size (employees)
3.8%Largest-city concentration · New York
Sep 20, 2026Page data refreshed

Companies by employee count

1-10
2,554
11-50
1,033
51-200
299
201-500
72
501-1,000
22
1,001-5,000
18
10001+
2

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 4,013 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 “investigation 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 11,857 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 20, 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.

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 “investigation firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many investigation firms are there based in the United States?

RevenueBase identified 4,013 company matches for investigation 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?

U.S. Security Associates, INC tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most investigation firms?

New York leads with 151 company records, followed by Houston (74) and Chicago (65).

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 11,857 professional contacts with verified work emails tracked across these 4,013 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 20, 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.