Company lists · Data refreshed September 2026
Top 25 IT security firms based in the United States
RevenueBase identified 6,070 IT security firms headquartered in the United States as of September 2026 and tracks 140,383 professional contacts across them, including 59,437 with verified work emails. New York is the largest hub.
This list covers IT security firms 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 IT security firms based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 18,431 contacts → | ||||
Indirect evidence “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: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 2 | 14,289 contacts → | ||||
Indirect evidence “Fortinet makes possible a digital world that we can always trust through its mission to protect people, devices, and data everywhere.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 3 | 11,169 contacts → | ||||
Partial evidence “Your backstage pass to the most epic cybersecurity solutions on the market for Endpoint, Network, Data and Cloud security.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 4 | 3,649 contacts → | ||||
Partial evidence “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: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 5 | 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. | |||||
| 6 | 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. | |||||
| 7 | 1,669 contacts → | ||||
Indirect evidence “BeyondTrust is the global cybersecurity leader protecting Paths to Privilege™.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 8 | 1,648 contacts → | ||||
Indirect evidence “Fortra delivers AI-amplified cybersecurity solutions that help organizations use and protect data with confidence.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 9 | 1,252 contacts → | ||||
Indirect evidence “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: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 10 | 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. | |||||
| 11 | 1,217 contacts → | ||||
Indirect evidence “On Dec.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 12 | 1,059 contacts → | ||||
Indirect evidence “WatchGuard® Technologies, Inc.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 13 | 947 contacts → | ||||
Indirect evidence “Coalfire is the premier Cybersecurity and Compliance Services leader for the tech, healthcare, and finance industries.(This page is maintained by Marketing.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 14 | 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. | |||||
| 15 | 889 contacts → | ||||
Partial evidence “Netenrich is redefining security operations by shifting the focus from "efficiency"(speed) to "efficacy"(comprehensive coverage).” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 16 | 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. | |||||
| 17 | 844 contacts → | ||||
Indirect evidence “Today’s threatscape is relentless.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 18 | 785 contacts → | ||||
Indirect evidence “ASK is now Convergence Networks!” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 19 | 696 contacts → | ||||
Indirect evidence “Protect Your Endpoints, Identities, Logs, and Employees.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 20 | 683 contacts → | ||||
Indirect evidence “BlueVoyant’s Cyber Defense Platform (CDP) integrates MDR, TPRM, and DRP into a seamless, scalable solution.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 21 | 660 contacts → | ||||
Partial evidence “With more than 30 years of experience partnering with global enterprises on complex business and IT initiatives, SDG is a trusted provider of advisory, transformation, and managed…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 22 | 651 contacts → | ||||
Indirect evidence “Vectra AI is the cybersecurity AI leader in protecting modern networks from modern attacks.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 23 | 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. | |||||
| 24 | 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. | |||||
| 25 | 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. | |||||
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: IT security firms. 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 IT security firms.
- Partial evidence
- Its own public description names part of IT security firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name IT security firms. 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 6,070 IT security firms based in the United States
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 59,437 reachable decision-makers.
Free signup · no credit card
IT security firms 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 6,070 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 IT security firms, 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 “IT security firms”. 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 IT security firms), 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 IT security firms, 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, 59,437 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.
IT security firms by metro
- IT security firms in New York172
- IT security firms in Austin109
- IT security firms in Houston107
- IT security firms in Washington103
- IT security firms in Atlanta101
- IT security firms in Dallas99
- IT security firms in Miami99
- IT security firms in Chicago95
- IT security firms in San Francisco88
- IT security firms in Tampa79
- IT security firms in San Diego59
- IT security firms in Los Angeles57
- IT security firms in Columbia53
- IT security firms in Denver53
- IT security firms in Arlington52
- IT security firms in Boston52
- IT security firms in Charlotte52
- IT security firms in Orlando49
- IT security firms in Seattle46
- IT security firms in Las Vegas44
- IT security firms in San Antonio42
- IT security firms in Phoenix41
- IT security firms in Reston40
- IT security firms in Alexandria39
- IT security firms in Baltimore34
- IT security firms in Wilmington34
- IT security firms in Fairfax33
- IT security firms in Raleigh33
- IT security firms in Huntsville32
- IT security firms in Mclean32
- IT security firms in Pittsburgh32
- IT security firms in Sheridan32
- IT security firms in Ashburn31
- IT security firms in Fort Lauderdale28
- IT security firms in Columbus27
- IT security firms in Dover27
- IT security firms in San Jose27
- IT security firms in Scottsdale27
- IT security firms in Colorado Springs26
- IT security firms in Philadelphia26
- IT security firms in Plano26
- IT security firms in Portland25
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 IT security firms, 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 IT security firms are there based in the United States?
RevenueBase identified 6,070 IT security firms 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 IT security firms?
New York leads with 172 headquartered companies, followed by Austin (109) and Houston (107).
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 59,437 verified decision-maker contacts tracked across these 6,070 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.
Ready to reach these companies? Verified emails and direct dials for all 6,070 IT security firms based in the United States. Start with a free account, no credit card.
Download this list →Related lists
IT security firms by geography
- IT security firms based in Adelaide, Australia
- IT security firms based in Brisbane, Australia
- IT security firms based in Canberra, Australia
- IT security firms based in Melbourne, Australia
- IT security firms based in Perth, Australia
- IT security firms based in Sydney, Australia
- IT security firms based in Belo Horizonte, Brazil
- IT security firms based in Brasilia, Brazil
- IT security firms based in Curitiba, Brazil
- IT security firms based in Rio De Janeiro, Brazil
- IT security firms based in Sao Paulo, Brazil
- IT security firms based in Calgary, Canada
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.
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- IT security firms based in Adelaide, Australia
- IT security firms based in Brisbane, Australia
- IT security firms based in Canberra, Australia
- IT security firms based in Melbourne, Australia
- IT security firms based in Perth, Australia
- IT security firms based in Sydney, Australia