Company lists · Data refreshed September 2026
Top 25 IT security firms based in Chicago, United States
RevenueBase identified 95 IT security firms headquartered in Chicago, United States as of September 2026 and tracks 3,188 professional contacts across them, including 1,697 with verified work emails. New York is the largest hub.
This list covers IT security firms headquartered in Chicago, 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 Chicago, United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 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. | |||||
| 2 | 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. | |||||
| 3 | 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. | |||||
| 4 | 166 contacts → | ||||
Partial evidence “Evolve Security is a technical cybersecurity firm and the home of Evolve Academy, offering holistic and advanced cybersecurity training and continuously ranked #1 in the U.S.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 5 | 69 contacts → | ||||
Partial evidence “Experiencing a security incident?” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 6 | 32 contacts → | ||||
Indirect evidence “We’ve moved!” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 7 | 29 contacts → | ||||
Partial evidence “SECURION was formed by industry problem-solving veterans that came together to bring their vision of a completely security focused, vendor agnostic, secure by design approach.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 8 | 27 contacts → | ||||
Partial evidence “In today’s digitally connected world, cyber security plays a crucial role.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 9 | 21 contacts → | ||||
Indirect evidence “At Ravenswood Technology Group, we don’t just offer our customers cybersecurity solutions – we deliver value and expertise you can rely on as needs and risks change.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 10 | 10 contacts → | ||||
Partial evidence “Cyber threats are relentless, and security teams are overwhelmed.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 11 | 10 contacts → | ||||
Indirect evidence “ArxNimbus brings visibility to every organization’s cybersecurity program, radically advancing how businesses understand and optimize for real resilience.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 12 | 9 contacts → | ||||
Partial evidence “HTA Technology Security Consulting (HTA) is a certified Woman-Owned, Small, Disadvantaged, Minority business with offices in Chicago, IL, and the Washington DC corridor.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 13 | 9 contacts → | ||||
Partial evidence “Data Defenders is at the forefront of Managed Cybersecurity Operations Providers (MCOP), specializing in safeguarding municipalities through our exclusive Regional Security…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 14 | 8 contacts → | ||||
Partial evidence “DataGuard Cybersecurity Without The Complexity DataGuard uses state-of-the-art industry resources to implement a multi-layer defense for each client’s unique cyber security needs.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 15 | 7 contacts → | ||||
Indirect evidence “At Cyber Bark, we bring 100 years of collective experience to the table, serving businesses across the US from our base in Illinois.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 16 | 7 contacts → | ||||
Partial evidence “JMA Consulting, LLC brings secure IT solutions to commercial clients in multiple industries nationwide.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 17 | 7 contacts → | ||||
Indirect evidence “Amol Solutions strives to be a leader in cybersecurity services for organizations of all sizes.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 18 | 6 contacts → | ||||
Indirect evidence “CrossRealms is a premier Cybersecurity and Managed Services provider with multiple locations in the United States, Canada, Europe, MENA region, and Asia.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 19 | 6 contacts → | ||||
Partial evidence “Clairos is a cybersecurity company that helps organizations build stronger, more manageable security programs through a practical, tailored approach.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 20 | 6 contacts → | ||||
Indirect evidence “Not auditors but real hackers.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 21 | 5 contacts → | ||||
Indirect evidence “Welcome to Network Aegis!” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 22 | 5 contacts → | ||||
Strong evidence “From server maintenance to disaster recovery, cloud solutions, IT network cyber security, asset management and more, TriForma Tech is in the business of making your business…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 23 | 5 contacts → | ||||
Indirect evidence “We operationalize, economize, and secure enterprise organizations by understanding their business outcomes and connecting them with proven, venture-backed startups recommended by…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 24 | 5 contacts → | ||||
Partial evidence “TeamWerks is an IT company based in the United States.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 25 | 4 contacts → | ||||
Partial evidence “ClearLP is a woman owned business specializing in digital security and network technology.” 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 95 IT security firms based in Chicago, United States
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IT security firms based in Chicago, United States at a glance
As of Sep 21, 2026Companies by employee count
Email recency for this list is measured across the whole United States list rather than for Chicago, so it is reported there. Company counts and contact totals on this page are exact for Chicago, over 95 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 Chicago, 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 Chicago 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, 1,697 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 in the United States
- 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 Chicago, United States?
RevenueBase identified 95 IT security firms headquartered in Chicago, 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?
Coalfire, headquartered in Chicago, 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 1,697 verified decision-maker contacts tracked across these 95 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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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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