Company lists · Data refreshed September 2026
Top 25 Managed security service providers based in the United States
RevenueBase identified 6,554 managed security service providers headquartered in the United States as of September 2026 and tracks 188,270 professional contacts across them, including 86,323 with verified work emails and 58,463 with mobile numbers. New York is the largest hub.
This list covers managed security service providers 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 service providers based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 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. | |||||
| 2 | 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. | |||||
| 3 | 11,169 | ||||
“Your backstage pass to the most epic cybersecurity solutions on the market for Endpoint, Network, Data and Cloud security.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 4 | 10,118 | ||||
“CrowdStrike (Nasdaq: CRWD), a global cybersecurity leader, has redefined modern security with the world’s most advanced cloud-native platform for protecting critical areas of…” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 5 | 3,649 | ||||
“We are a crowdsourced security company that safeguards organizations' assets from sophisticated threat actors before they can strike-by uniting our customers with trusted hackers…” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 6 | 3,447 | ||||
“Trellix is a global cybersecurity company delivering intelligence-led cyber resilience for security-conscious organizations at any stage of their journey.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 7 | 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. | |||||
| 8 | 3,052 | ||||
“SentinelOne is the world's leading AI-powered cybersecurity platform.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 9 | 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. | |||||
| 10 | 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. | |||||
| 11 | 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. | |||||
| 12 | 1,648 | ||||
“Fortra delivers AI-amplified cybersecurity solutions that help organizations use and protect data with confidence.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 13 | 1,285 | ||||
“ReliaQuest exists to Make Security Possible.” 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 | 1,181 | ||||
“As AI-driven vulnerability and exploitation accelerate attack velocity to machine speed, Forescout is a foundational cyber defense layer that allows organizations to segment and…” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 18 | 1,059 | ||||
“WatchGuard® Technologies, Inc.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 19 | 947 | ||||
“Coalfire is the premier Cybersecurity and Compliance Services leader for the tech, healthcare, and finance industries.(This page is maintained by Marketing.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 20 | 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. | |||||
| 21 | 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. | |||||
| 22 | 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. | |||||
| 23 | 844 | ||||
“Today’s threatscape is relentless.” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 24 | 785 | ||||
“ASK is now Convergence Networks!” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 25 | 752 | ||||
“Bitsight is the global leader in cyber risk intelligence, leveraging advanced AI to empower organizations with precise insights derived from the industry’s most extensive external…” Source: company website · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
Showing 25 of 6,554 managed security service providers based in the United States
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Managed security service providers 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 service providers, 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 service providers”. 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 service providers, 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, 86,323 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 service providers by metro
- Managed security service providers in New York200
- Managed security service providers in Houston120
- Managed security service providers in Austin117
- Managed security service providers in Atlanta114
- Managed security service providers in Washington107
- Managed security service providers in Miami106
- Managed security service providers in Chicago100
- Managed security service providers in Dallas100
- Managed security service providers in Tampa94
- Managed security service providers in San Francisco86
- Managed security service providers in Charlotte61
- Managed security service providers in Los Angeles60
- Managed security service providers in Columbia56
- Managed security service providers in Arlington54
- Managed security service providers in San Diego53
- Managed security service providers in Denver52
- Managed security service providers in Orlando52
- Managed security service providers in Boston51
- Managed security service providers in Las Vegas51
- Managed security service providers in San Antonio48
- Managed security service providers in Phoenix47
- Managed security service providers in Seattle39
- Managed security service providers in Reston38
- Managed security service providers in Wilmington38
- Managed security service providers in Alexandria37
- Managed security service providers in Irvine36
- Managed security service providers in Mclean36
- Managed security service providers in Sheridan36
- Managed security service providers in Fairfax34
- Managed security service providers in Raleigh33
- Managed security service providers in Huntsville32
- Managed security service providers in Portland32
- Managed security service providers in San Jose31
- Managed security service providers in Baltimore30
- Managed security service providers in Pittsburgh30
- Managed security service providers in Scottsdale30
- Managed security service providers in Plano29
- Managed security service providers in Fort Lauderdale28
- Managed security service providers in Colorado Springs27
- Managed security service providers in Ashburn26
- Managed security service providers in Dover26
- Managed security service providers in Richmond25
Frequently asked
How many managed security service providers are there based in the United States?
RevenueBase identified 6,554 managed security service providers 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?
Palo Alto Networks, headquartered in Santa Clara, tops this list with the largest team on record.
Which city has the most managed security service providers?
New York leads with 200 headquartered companies, followed by Houston (120) and Austin (117).
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 86,323 verified decision-maker contacts tracked across these 6,554 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 service providers by geography
- Managed security service providers based in the United Kingdom
- Managed security service providers based in Canada
- Managed security service providers based in Australia
- Managed security service providers based in France
- Managed security service providers based in Brazil
- Managed security service providers based in Germany
- Managed security service providers based in Spain
- Managed security service providers based in the Netherlands
- Managed security service providers based in Italy
- Managed security service providers based in South Africa
- Managed security service providers based in Mexico
- Managed security service providers 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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