Company lists · Data refreshed September 2026

Top 25 Investigative agencies based in the United States

RevenueBase identified 1,827 company matches for investigative agencies associated with the United States as of September 2026 and tracks 38,642 professional contacts across them, including 7,387 with verified work emails. New York is the largest hub.

This list covers company matches for investigative agencies 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
1,827Companies
38,642Contacts tracked
7,387Verified emails
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The 25 largest investigative agencies based in the United States

Ranked by team size
Top 25 of 1,827 company matches for investigative agencies 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 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
2Exact matchTallahassee, FL, United StatesHQ recorded Sep 20, 20261,001-5,000676 contacts →

Exact match

“Our Mission To promote public safety and strengthen domestic security by providing services in partnership with local, state, and federal criminal justice agencies to prevent…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
3Exact 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
4Exact 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
5Exact 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
6Exact 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
7Exact 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
8Exact 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
9Exact matchFort Worth, TX, United StatesHQ recorded Sep 20, 202651-200146 contacts →

Exact match

“A federally qualified Small Business, IDS offers end to end investigative solutions tailored to meet the specific needs of our clients.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
10Exact matchNew York, NY, United StatesHQ recorded Sep 20, 202651-200129 contacts →

Exact match

“Beau Dietl & Associates is a premier private investigation firm based in New York City with offices in New Jersey, Florida, and California.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
11Exact matchChicago, IL, United StatesHQ recorded Sep 20, 202651-200124 contacts →

Exact match

“The City of Chicago Office of Inspector General (OIG) is an independent, nonpartisan oversight agency whose mission is to promote economy, effectiveness, efficiency, and integrity…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
12Exact matchNorth Haven, CT, United StatesHQ recorded Sep 20, 2026501-1,000119 contacts →

Exact match

“Knowledge is power" Whether you are an insurance company, TPA, insurance defense law firm, risk manager, private law firm, or corporation / business owner, we at Lemieux &…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
13Exact matchNew York, NY, United StatesHQ recorded Sep 20, 202651-200112 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
14Exact matchLos Angeles, TX, United StatesHQ recorded Sep 20, 202651-200107 contacts →

Exact match

“Alias Intelligence is a leading background investigations and due diligence company delivering the information and insights our clients need to grow and navigate their businesses.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
15Exact matchTroy, MI, United StatesHQ recorded Sep 20, 2026201-500104 contacts →

Exact match

“The Robison Group is an agency of professional investigators and support teams offering surveillance, SIU claims, business risk mitigation and comprehensive desktop investigation…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
16Exact matchUnited StatesHQ recorded Sep 20, 2026201-50094 contacts →

Exact match

“Why Becker & Company?”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
17Exact matchBethesda, MD, United StatesHQ recorded Sep 20, 202651-20093 contacts →

Exact match

“RosettiStarr provides cutting-edge intelligence, investigations, corporate risk and cyber security services to management teams, attorneys and investors worldwide.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
18Exact matchPark Ridge, IL, United StatesHQ recorded Sep 20, 2026201-50084 contacts →

Exact match

“Marshall Investigative Group, division of Sphere Investigations, is a recognized leader in fraud and corporate investigations with more than 30 years of experience across North…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
19Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-50082 contacts →

Exact match

“AJ Squared Security, Inc.(AJ2), is a privately owned security organization founded in May 2003 and incorporated in November 2003.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
20Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-50072 contacts →

Exact match

“Integrated Security Services, Inc.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
21Exact matchMonaca, PA, United StatesHQ recorded Sep 20, 2026201-50069 contacts →

Exact match

“CSI is a full-service investigative firm that delivers key facts to give our clients an actionable advantage in a wide range of situations.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
22Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-50068 contacts →

Exact match

“At CITY SAFE PARTNERS SECURITY, we create solutions and put systems in place to ensure that people and businesses are secure.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
23Exact matchWoburn, MA, United StatesHQ recorded Sep 20, 2026201-50067 contacts →

Exact match

“Claims Bureau USA has been providing Insurers, TPA's and their defense counsel with quality, in-depth investigative services since 1956.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
24Exact matchWashington, DC, United StatesHQ recorded Sep 20, 202611-5066 contacts →

Exact match

“Investigative Group International (IGI) is the premier investigative firm conducting independent, high-touch investigations worldwide.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
25Exact matchPlymouth, MI, United StatesHQ recorded Sep 20, 2026201-50064 contacts →

Exact match

“A.S.K.”

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

Showing 25 of 1,827 investigative agencies based in the United States

See the full list, filter by size, metro and specialty, and access 7,387 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Investigative agencies based in the United States at a glance

As of Sep 20, 2026
19.1%Verified-email coverage
21.2Average contacts per company
1-10Median size (employees)
3.1%Largest-city concentration · New York
Sep 20, 2026Page data refreshed

Companies by employee count

1-10
1,176
11-50
431
51-200
141
201-500
43
501-1,000
14
1,001-5,000
14
5,001-10,000
1
10001+
3

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 1,827 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 “investigative agencies” 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 7,387 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 “investigative agencies”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many investigative agencies are there based in the United States?

RevenueBase identified 1,827 company matches for investigative agencies 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?

Omniplex World Services Corporation tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most investigative agencies?

New York leads with 56 company records, followed by Washington (43) and Houston (28).

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 7,387 professional contacts with verified work emails tracked across these 1,827 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.