Company lists · Data refreshed September 2026
Top 25 Investigative agencies worldwide
RevenueBase identified 3,951 investigative agencies worldwide as of September 2026 and tracks 81,867 professional contacts across them, including 13,477 with verified work emails. The United States is the largest market and London the largest hub.
This list covers investigative agencies worldwide, 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 20, 2026. Country and city lists for investigative agencies follow the table.
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 investigative agencies worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 1,544 contacts → | ||||
Indirect evidence “La labor de la Contraloría es eminentemente fiscalizadora; de carácter jurídico, contable y financiero, pues está destinada a cautelar el principio de legalidad, es decir…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 2 | 946 contacts → | ||||
Strong evidence “The Swedish Prosecution Authority work in collaboration with other authorities to ensure that criminal investigations are carried out efficiently with legal certainty.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 3 | 677 contacts → | ||||
Strong evidence “OMNIPLEX World Services Corporation is a leader and innovator in delivering professional background investigations, intelligence support, and physical security services to…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 4 | 676 contacts → | ||||
Indirect evidence “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…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 5 | 572 contacts → | ||||
Strong evidence “DK Security is unique in that it offers a single company for a wide ranging availability of security and investigative services.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 6 | 560 contacts → | ||||
Indirect evidence “Rund 2’200 Personen arbeiten in der Direktion der Justiz und des Innern, im Generalsekretariat, in 4 Ämtern, 3 Fachämtern, 4 Fachstellen und zwei angegliederten Bereichen.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 7 | 550 contacts → | ||||
Strong evidence “The Special Investigating Unit is established in terms of the Special Investigating Units and Special Tribunals Act 74 of 1996.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 8 | 518 contacts → | ||||
Strong evidence “CoventBridge Group is the leading worldwide full service investigation solutions company providing: Surveillance, SIU and Compliance, Claims Investigation, Counter-Fraud Programs…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 9 | 511 contacts → | ||||
Strong evidence “Founded in 1982, Ranger American is a professional security organization with an extensive background in the security and investigation fields.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 10 | 386 contacts → | ||||
Indirect evidence “Dibentuk berdasarkan Undang-Undang Nomor 30 Tahun 2002 tentang Komisi Pemberantasan Tindak Pidana Korupsi, Komisi Pemberantasan Korupsi (KPK) diberi amanat melakukan pemberantasan…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 11 | 344 contacts → | ||||
Indirect evidence “Investigate fraud, waste, and abuse in the NYS Medicaid program.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 12 | 327 contacts → | ||||
Strong evidence “DigiStream Investigations is a full-service private investigation firm specializing in insurance defense and legal support services.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 13 | 325 contacts → | ||||
Indirect evidence “De Algemene Rekenkamer controleert of rijksoverheid geld uitgeeft en beleid uitvoert zoals het de bedoeling was.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 14 | 321 contacts → | ||||
Indirect evidence “Vi rekrutterer personer med høy kompetanse til et bredt og tverrfaglig miljø.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 15 | 312 contacts → | ||||
Indirect evidence “Investgation of Civil Fraud through out the state.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 16 | 285 contacts → | ||||
Indirect evidence “Riksrevisionen är en oberoende myndighet under riksdagen med uppdrag att granska statens verksamhet.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 17 | 214 contacts → | ||||
Indirect evidence “Frasco has hundreds of investigators and regional offices located throughout the country.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 18 | 214 contacts → | ||||
Strong evidence “Advantage Investigations is a nationwide leader in the industry for investigative services.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 19 | 146 contacts → | ||||
Strong evidence “A federally qualified Small Business, IDS offers end to end investigative solutions tailored to meet the specific needs of our clients.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 20 | 129 contacts → | ||||
Strong evidence “Beau Dietl & Associates is a premier private investigation firm based in New York City with offices in New Jersey, Florida, and California.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 21 | 126 contacts → | ||||
Strong evidence “Mediprobe Consultancy Services Pvt Ltd is a leading insurance investigation agency with over 15 years of experience.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 22 | 124 contacts → | ||||
Indirect evidence “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…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 23 | 119 contacts → | ||||
Indirect evidence “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 &…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 24 | 112 contacts → | ||||
Indirect evidence Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 25 | 111 contacts → | ||||
Indirect evidence “Bijdragen aan een rechtvaardige en veilige samenleving.” Source: RevenueBase Database · checked Sep 20, 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: investigative agencies. 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 investigative agencies.
- Partial evidence
- Its own public description names part of investigative agencies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name investigative agencies. 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 3,951 investigative agencies worldwide
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 13,477 reachable decision-makers.
Free signup · no credit card
Investigative agencies worldwide at a glance
As of Sep 20, 2026Companies by employee count
Email recency is reported on each country list linked below.
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 investigative agencies, 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.
- Coverage
- Every country. Country and city lists for investigative agencies are linked below.
- What qualifies
- Companies worldwide whose own description of what they do matches “investigative agencies”. 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 investigative agencies), 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 investigative agencies, and records with no verified work email.
- 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, 13,477 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 20, 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.
Investigative agencies by location
11 lists · largest firstEvery Investigative agencies list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Investigative agencies based in the United States1,827
- Investigative agencies based in Italy221
- Investigative agencies based in the United Kingdom183
- Investigative agencies based in Canada124
- Investigative agencies based in Spain103
- Investigative agencies based in Australia95
- Investigative agencies based in the Netherlands75
- Investigative agencies based in South Africa41
Cities
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 investigative agencies, 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 investigative agencies are there worldwide?
RevenueBase identified 3,951 investigative agencies worldwide 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?
Contraloría General DE LA República, headquartered in Santiago, tops this list with the largest team on record.
Which country has the most investigative agencies?
The United States leads with 1,827 companies, followed by Italy (221) and the United Kingdom (183). Every investigative agencies list by country and city is linked on this page.
Which city has the most investigative agencies?
London leads with 62 headquartered companies, followed by New York (53) and Washington (44).
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 13,477 verified decision-maker contacts tracked across these 3,951 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 20, 2026.
Ready to reach these companies? Verified emails and direct dials for all 3,951 investigative agencies worldwide. Start with a free account, no credit card.
Download this list →Related lists
Browse the directory
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.