Company lists · Data refreshed September 2026
Top 16 Security investigation companies based in Washington, United States
RevenueBase identified 38 security investigation companies headquartered in Washington, United States as of September 2026 and tracks 660 professional contacts across them, including 79 with verified work emails. Across the United States, New York is the largest hub for this category (117 companies); Washington has 38.
This list covers security investigation companies headquartered in Washington, 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 29, 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 16 largest security investigation companies based in Washington, United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 142 contacts → | ||||
Partial evidence “PSA is a global due diligence and investigations firm headquartered in Washington, DC.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 2 | 66 contacts → | ||||
Partial evidence “Investigative Group International (IGI) is the premier investigative firm conducting independent, high-touch investigations worldwide.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 3 | 63 contacts → | ||||
Partial evidence “Established in 1974, Colorado Security Agency (CSA) is a professional security provider based in Georgetown Washington DC.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 4 | 37 contacts → | ||||
Partial evidence “Global Security & Innovative Strategies (GSIS) leverages its extensive private sector, homeland, public security, public sector and international expertise to provide…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 5 | 20 contacts → | ||||
Partial evidence “Hire Police is a physical security company that provides on-site physical security and roving security patrols using unarmed guards and armed officers.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 6 | 19 contacts → | ||||
Partial evidence “At Georgetown Protective Services, we provide top-tier security solutions tailored to your needs.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 7 | 11 contacts → | ||||
Partial evidence “Personnel Security Professionals was started by two veterans who have served as government and contract subject matter experts in Industry and Personnel Security for more than 30…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 8 | 11 contacts → | ||||
Partial evidence “At USP Security, we understand that safety is paramount, and we are dedicated to providing top-notch armed and unarmed security services for a diverse range of industries.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 9 | 6 contacts → | ||||
Partial evidence “Forward Global conducts investigative due diligence, business intelligence research, and international risk assessments for financial institutions, corporations, and law firms.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 10 | 5 contacts → | ||||
Indirect evidence “A.T.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 11 | 4 contacts → | ||||
Strong evidence “What We Do: We provide CFOs, corporate security directors, and business professionals with investigative services, consultations, and risk assessments to help our clients make the…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 12 | 4 contacts → | ||||
Strong evidence “XK Group provides advisory services Due Diligence Security Assessments Competitive Intelligence Background Investigations Crisis Management Insider Threat Analysis Fraud…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 13 | 3 contacts → | ||||
Partial evidence “Axios Security Group (ASG) is a veteran owned and operated Physical and Digital Security Consulting Company.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 14 | 3 contacts → | ||||
Strong evidence “WCD Business Solutions provides full-scope background investigations, private investigation services, surveillance, personnel security staffing, case management system…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 15 | 2 contacts → | ||||
Partial evidence “Butler Investigations is an investigative services firm providing comprehensive solutions to attorneys and law firms across the country.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 16 | 1 contacts → | ||||
Partial evidence “At Night Owl Protective Services we provide common sense, cost effective security protective services for any commercial or residential site in the nation's capital.” Source: RevenueBase Database · checked Sep 29, 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: security investigation companies. 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 security investigation companies.
- Partial evidence
- Its own public description names part of security investigation companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name security investigation companies. 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 16 of 38 security investigation companies based in Washington, United States
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Security investigation companies based in Washington, United States at a glance
As of Sep 29, 2026Companies by employee count
Email recency for this list is measured across the whole United States list rather than for Washington, so it is reported there. Company counts and contact totals on this page are exact for Washington, over 38 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 security investigation companies, 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 Washington, United States whose own description of what they do matches “security investigation companies”. 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 security investigation companies), 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 security investigation companies, and records with no verified work email. Companies headquartered outside Washington 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, 79 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 29, 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.
Security investigation companies by metro in the United States
- Security investigation companies in New York117
- Security investigation companies in Los Angeles73
- Security investigation companies in Houston71
- Security investigation companies in Chicago53
- Security investigation companies in Miami52
- Security investigation companies in Atlanta43
- Security investigation companies in Phoenix32
- Security investigation companies in Austin30
- Security investigation companies in Denver25
- Security investigation companies in Las Vegas25
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 security investigation companies, 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 security investigation companies are there based in Washington, United States?
RevenueBase identified 38 security investigation companies headquartered in Washington, 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?
PSA, headquartered in Washington, tops this list with the largest team on record.
Which city in the United States has the most security investigation companies?
New York leads the United States with 117 headquartered companies, followed by Los Angeles (73) and Houston (71). Washington has 38.
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 79 verified decision-maker contacts tracked across these 38 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 29, 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.
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