Company lists · Data refreshed September 2026
Top 25 Managed IT security services providers based in the United States
RevenueBase identified 6,736 managed IT security services providers headquartered in the United States as of September 2026 and tracks 112,457 professional contacts across them, including 49,863 with verified work emails. New York is the largest hub.
This list covers managed IT security services 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, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 21, 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 25 largest managed IT security services providers based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 3,145 contacts → | ||||
Indirect evidence “Every year new technologies, vendors, and solutions emerge-yet despite this constant innovation, high-profile breaches are all over the headlines.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 2 | 3,058 contacts → | ||||
Strong evidence “Qualys, Inc.(NASDAQ: QLYS) is a leading provider of disruptive cloud-based security, compliance and IT solutions with more than subscription customers worldwide, including a…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 3 | 2,222 contacts → | ||||
Indirect evidence “Optiv is the cyber advisory and solutions leader, delivering strategic and technical expertise to nearly companies across every major industry.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 4 | 1,906 contacts → | ||||
Strong evidence “Established in 1995, GURU is an IT managed service provider that specializes in infrastructure support, systems integration, data architecture, data hosting, and cloud services.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 5 | 1,749 contacts → | ||||
Partial evidence “ePlus is a customer-first, services-led, results-driven and trusted industry leader that helps organizations secure, modernize, optimize, and scale every aspect of their IT…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 6 | 1,232 contacts → | ||||
Partial evidence “GuidePoint Security provides trusted cybersecurity expertise, solutions, and services that help organizations make informed decisions and minimize risk.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 7 | 1,181 contacts → | ||||
Indirect evidence “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: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 8 | 1,059 contacts → | ||||
Indirect evidence “WatchGuard® Technologies, Inc.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 9 | 1,037 contacts → | ||||
Partial evidence “Synoptek is a leading global managed services provider and technology consulting firm that delivers transformative business results.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 10 | 944 contacts → | ||||
Strong evidence “Secureworks, a Sophos Company, empowers organizations worldwide with advanced Managed Detection and Response (MDR) services, our security operations platform Taegis XDR, and…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 11 | 904 contacts → | ||||
Indirect evidence “ZeroFox is the solution to discover, validate, and disrupt external cyber threats before they harm revenue or reputation.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 12 | 874 contacts → | ||||
Indirect evidence “Trustwave, a LevelBlue Company, is a globally recognized cybersecurity leader that reduces cyber risk and fortifies organizations against disruptive and damaging cyber threats.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 13 | 844 contacts → | ||||
Indirect evidence “Today’s threatscape is relentless.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 14 | 751 contacts → | ||||
Indirect evidence “TPx is the reliable sidekick every growing business deserves, powering your tech while you take the lead.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 15 | 731 contacts → | ||||
Partial evidence “As a leading global provider of security and cloud-based software solutions purpose-built for MSPs, Datto, a Kaseya company, believes there is no limit to what SMBs can achieve…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 16 | 710 contacts → | ||||
Indirect evidence “We are Architects of Change.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 17 | 696 contacts → | ||||
Indirect evidence “Protect Your Endpoints, Identities, Logs, and Employees.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 18 | 687 contacts → | ||||
Indirect evidence “Customers of all sizes globally rely on Simeio to help secure their organizations.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 19 | 683 contacts → | ||||
Partial evidence “With 30 years of experience as a trusted managed services provider, we're your dedicated partner in navigating the complex world of technology, so you can focus on growing your…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 20 | 641 contacts → | ||||
Partial evidence “At Network Intelligence, we combine our team of 500+ security professionals with Transilience – our cutting-edge AI platform.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 21 | 629 contacts → | ||||
Partial evidence “Telos Corporation (NASDAQ: TLS) empowers and protects the world’s most security-conscious organizations with efficient, adaptable, and secure solutions that safeguard people…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 22 | 628 contacts → | ||||
Indirect evidence “VikingCloud delivers battle-tested cybersecurity and compliance solutions that simply work.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 23 | 574 contacts → | ||||
Partial evidence “Integris is a national leader in future-ready Managed Services, delivering innovative solutions that drive digital maturity for small and midsize businesses.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 24 | 523 contacts → | ||||
Partial evidence “UltraViolet Cyber is the only security operations partner that unifies red, blue, and purple team capabilities into one integrated program, finding what's vulnerable, stopping…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 25 | 505 contacts → | ||||
Indirect evidence “At Ntiva, growing people (our employees, partners, and clients) is our mission.” Source: RevenueBase Database · checked Sep 21, 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: managed IT security services providers. 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 managed IT security services providers.
- Partial evidence
- Its own public description names part of managed IT security services providers, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name managed IT security services providers. 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 6,736 managed IT security services providers based in the United States
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Managed IT security services providers based in the United States at a glance
As of Sep 21, 2026Companies by employee count
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 6,736 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 managed IT security services providers, 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 the United States whose own description of what they do matches “managed IT security services providers”. 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 managed IT security services providers), 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 managed IT security services 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 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, 49,863 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 21, 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 IT security services providers by metro
- Managed IT security services providers in New York198
- Managed IT security services providers in Houston147
- Managed IT security services providers in Miami96
- Managed IT security services providers in Austin95
- Managed IT security services providers in Dallas89
- Managed IT security services providers in Atlanta85
- Managed IT security services providers in Chicago81
- Managed IT security services providers in Tampa79
- Managed IT security services providers in Los Angeles61
- Managed IT security services providers in Charlotte58
- Managed IT security services providers in Phoenix57
- Managed IT security services providers in San Diego52
- Managed IT security services providers in San Francisco52
- Managed IT security services providers in Washington52
- Managed IT security services providers in Las Vegas49
- Managed IT security services providers in Denver48
- Managed IT security services providers in Irvine48
- Managed IT security services providers in San Antonio43
- Managed IT security services providers in Columbia35
- Managed IT security services providers in Wilmington35
- Managed IT security services providers in Boston34
- Managed IT security services providers in Alexandria32
- Managed IT security services providers in Orlando32
- Managed IT security services providers in Portland32
- Managed IT security services providers in Scottsdale32
- Managed IT security services providers in Plano29
- Managed IT security services providers in Arlington28
- Managed IT security services providers in San Jose28
- Managed IT security services providers in Fort Lauderdale26
- Managed IT security services providers in Cincinnati25
- Managed IT security services providers in Seattle25
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 managed IT security services providers, 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 managed IT security services providers are there based in the United States?
RevenueBase identified 6,736 managed IT security services 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?
Arctic Wolf, headquartered in Eden Prairie, tops this list with the largest team on record.
Which city has the most managed IT security services providers?
New York leads with 198 headquartered companies, followed by Houston (147) and Miami (96).
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 49,863 verified decision-maker contacts tracked across these 6,736 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 21, 2026.
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Managed IT security services providers by geography
- Managed IT security services providers based in Brisbane, Australia
- Managed IT security services providers based in Melbourne, Australia
- Managed IT security services providers based in Sydney, Australia
- Managed IT security services providers based in Belo Horizonte, Brazil
- Managed IT security services providers based in Rio De Janeiro, Brazil
- Managed IT security services providers based in Sao Paulo, Brazil
- Managed IT security services providers based in Calgary, Canada
- Managed IT security services providers based in Edmonton, Canada
- Managed IT security services providers based in Mississauga, Canada
- Managed IT security services providers based in Montreal, Canada
- Managed IT security services providers based in Ottawa, Canada
- Managed IT security services providers based in Toronto, Canada
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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