Company lists · Data refreshed September 2026
Top 25 Managed security services companies based in the United States
RevenueBase identified 4,323 managed security services companies headquartered in the United States as of September 2026 and tracks 191,612 professional contacts across them, including 63,019 with verified work emails and 61,369 with mobile numbers. New York is the largest hub.
This list covers managed security services companies 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, how directly it supports the match, and when it was last checked. Data refreshed September 5, 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.
The 25 largest managed security services companies based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 38,634 | ||||
“Securitas knows Security.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 2 | 18,431 | ||||
“Palo Alto Networks, the global cybersecurity leader, is shaping the cloud-centric future with technology that is transforming the way people and organizations operate.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 3 | 14,289 | ||||
“Fortinet makes possible a digital world that we can always trust through its mission to protect people, devices, and data everywhere.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 4 | 4,358 | ||||
“We've merged!” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 5 | 3,592 | ||||
“U.S.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 6 | 3,145 | ||||
“Every year new technologies, vendors, and solutions emerge-yet despite this constant innovation, high-profile breaches are all over the headlines.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 7 | Rapid7Partial evidence | 2,822 | |||
“Rapid7, Inc.(NASDAQ: RPD) is a global leader in AI-powered managed cybersecurity operations, trusted to advance organizations’ cyber resilience.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 8 | 2,266 | ||||
“Andy Frain Services.America's leading provider of integrated solutions to security and events needs for over 90 years.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 9 | 2,222 | ||||
“Optiv is the cyber advisory and solutions leader, delivering strategic and technical expertise to nearly companies across every major industry.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 10 | 2,157 | ||||
“Barracuda is a leading global cybersecurity company providing complete protection against complex threats for all size business.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 11 | 1,639 | ||||
“Sunstates Security, LLC is one of the industry's leading providers of contract security services with a differentiated approach to providing successful, cost-effective, quality…” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 12 | 1,406 | ||||
“As of May 2016, Protection 1 and ADT merged together to become the leading company in the electronic security industry.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 13 | 1,399 | ||||
“Weiser Security Services is the 11th largest security service provider in the U.S.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 14 | 1,252 | ||||
“Thales is a global leader in cybersecurity, helping the most trusted organizations in the world protect their most critical applications, data, and identities anywhere at scale.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 15 | 1,232 | ||||
“GuidePoint Security provides trusted cybersecurity expertise, solutions, and services that help organizations make informed decisions and minimize risk.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 16 | 1,217 | ||||
“On Dec.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 17 | 1,138 | ||||
“At Titan Security Group, we understand that each client is unique, with specific security needs shaped by the type of property and its location.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 18 | 1,120 | ||||
“Per Mar Security Services is the largest full-service security solutions provider in the Midwest.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 19 | 1,062 | ||||
“Founded in 1982, St.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 20 | 1,059 | ||||
“WatchGuard® Technologies, Inc.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 21 | 944 | ||||
“Secureworks, a Sophos Company, empowers organizations worldwide with advanced Managed Detection and Response (MDR) services, our security operations platform Taegis XDR, and…” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 22 | 932 | ||||
“As an established mid-market company, clients throughout the country entrust us as the best-qualified firm to protect their highest-value assets – while delivering the quality…” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 23 | 904 | ||||
“ZeroFox is the solution to discover, validate, and disrupt external cyber threats before they harm revenue or reputation.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 24 | 889 | ||||
“Netenrich is redefining security operations by shifting the focus from "efficiency"(speed) to "efficacy"(comprehensive coverage).” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 25 | 874 | ||||
“Trustwave, a LevelBlue Company, is a globally recognized cybersecurity leader that reduces cyber risk and fortifies organizations against disruptive and damaging cyber threats.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
Showing 25 of 4,323 managed security services companies based in the United States
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Managed security services companies based in the United States at a glance
As of Sep 5, 2026Companies by employee count
Verified emails by last verification
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 managed security services companies, so some rows will be adjacent to the category rather than pure plays. The description and evidence 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 SmartSearch, 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 “managed security services companies”. Matching reads each company's description, not its industry code or its name.
- What we exclude
- Companies whose own description does not clearly place them among managed security services companies, 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 an evidence 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, 63,019 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 5, 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.
Managed security services companies by metro
- Managed security services companies in New York103
- Managed security services companies in Houston85
- Managed security services companies in Miami81
- Managed security services companies in Austin65
- Managed security services companies in Chicago64
- Managed security services companies in Dallas63
- Managed security services companies in Atlanta60
- Managed security services companies in Los Angeles57
- Managed security services companies in Tampa47
- Managed security services companies in San Francisco43
- Managed security services companies in Washington43
- Managed security services companies in Charlotte39
- Managed security services companies in Las Vegas38
- Managed security services companies in San Diego37
- Managed security services companies in Denver35
- Managed security services companies in Phoenix34
- Managed security services companies in Irvine30
- Managed security services companies in Arlington26
- Managed security services companies in Columbia26
- Managed security services companies in Orlando26
- Managed security services companies in Scottsdale25
- Managed security services companies in Wilmington25
Frequently asked
How many managed security services companies are there based in the United States?
RevenueBase identified 4,323 managed security services companies 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?
Securitas Security Services Usa, INC, headquartered in Parsippany, tops this list with the largest team on record.
Which city has the most managed security services companies?
New York leads with 103 headquartered companies, followed by Houston (85) and Miami (81).
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 63,019 verified decision-maker contacts tracked across these 4,323 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 5, 2026.
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Managed security services companies by geography
- Managed security services companies based in the United Kingdom
- Managed security services companies based in Brazil
- Managed security services companies based in Canada
- Managed security services companies based in Australia
- Managed security services companies based in France
- Managed security services companies based in Germany
- Managed security services companies based in Italy
- Managed security services companies based in South Africa
- Managed security services companies based in Spain
- Managed security services companies based in the Netherlands
- Managed security services companies based in Mexico
- Managed security services companies based in Israel
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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.
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