Company lists · Data refreshed September 2026
Top 25 Security auditing firms worldwide
RevenueBase identified 9,232 security auditing firms worldwide as of September 2026 and tracks 103,034 professional contacts across them, including 36,431 with verified work emails and 16,340 with mobile numbers. The United States is the largest market and London the largest hub.
This list covers security auditing firms worldwide, 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 6, 2026. Country and city lists for security auditing firms follow the table.
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 security auditing firms worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 2 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 3 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 4 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 5 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 6 | 844 contacts → | ||||
Indirect evidence “Today’s threatscape is relentless.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 7 | 798 contacts → | ||||
Indirect evidence “A-LIGN is the leading provider of high-quality, efficient cybersecurity compliance programs.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 8 | 705 contacts → | ||||
Partial evidence “Get a free, powerful security assessment with personalised recommendations, the same analysis that costs from IT Consultancies.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 9 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 10 | 639 contacts → | ||||
Indirect evidence “I-TRACING, pure player and cybersecurity service provider leader in France, supports over 600 clients around the world in managing their cyber risks, from anticipating threats to…” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 11 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 12 | 628 contacts → | ||||
Indirect evidence “VikingCloud delivers battle-tested cybersecurity and compliance solutions that simply work.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 13 | 535 contacts → | ||||
Partial evidence “Funded by world-class investors, including Evolution Equity Partners, Silver Lake Partners, Sequoia Capital, GV, Riverwood Capital, and others, SecurityScorecard is the global…” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 14 | 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 6, 2026Thanks. The Data Team will review it. | |||||
| 15 | 506 contacts → | ||||
Indirect evidence “Founded in 2008, OWN is a Pure Player in cybersecurity, with offices in Paris, Rennes and Toulouse, but with a presence throughout France with its fully remote employees.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 16 | 502 contacts → | ||||
Partial evidence “SecurityHQ, a global cybersecurity company pioneering Security Performance Engineering for stronger operational performance and resilience.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 17 | 473 contacts → | ||||
Indirect evidence “At Aujas Cybersecurity, we specialize in building and transforming cybersecurity postures to help businesses effectively mitigate risks.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 18 | 441 contacts → | ||||
Partial evidence “Palo Alto Networks Unit 42 brings together world-renowned threat researchers with an elite team of incident responders and security consultants to create an intelligence-driven…” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 19 | 399 contacts → | ||||
Indirect evidence “A SAFEWAY empresa que integra a plataforma de cibersegurança do Grupo Stefanini se une a Protega.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 20 | 398 contacts → | ||||
Partial evidence “ACPL Systems is a pure-play cybersecurity services company focused on helping organisations translate security investments into measurable outcomes.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 21 | 392 contacts → | ||||
Partial evidence “Kudelski Security is a premier cybersecurity solutions provider, working with the most security-conscious organizations in Europe and across the United States.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 22 | 386 contacts → | ||||
Indirect evidence “Progress is our motivation because we are convinced that it will lead us to a successful future – independent of industries, companies and social classes.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 23 | 382 contacts → | ||||
Indirect evidence “NEVERHACK is a French group specialized in cybersecurity for over 40 years.” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 24 | 365 contacts → | ||||
Indirect evidence “Welcome to IBN Technologies, LLC, Your Trusted Partner in Cybersecurity, Cloud, and Finance Solutions With 26+ years of expertise, IBN Technologies leads in delivering integrated…” Source: RevenueBase Database · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 25 | 363 contacts → | ||||
Partial evidence “eSec Forte® Technologies is a CMMi Level 3 certified Global Consulting and IT Security Services company with offerings across Cloud Security, Cyber Forensics, Malware Detection…” Source: RevenueBase Database · checked Sep 6, 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: security auditing 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 security auditing firms.
- Partial evidence
- Its own public description names part of security auditing firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name security auditing 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 9,232 security auditing firms worldwide
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Security auditing firms worldwide at a glance
As of Sep 6, 2026Companies by employee count
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 security auditing 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.
- Coverage
- 35 countries, largest first: the United States, the United Kingdom, India, France, Canada, Australia, Brazil, Germany, the Netherlands, Spain and 25 more. Country and city lists for security auditing firms are linked below.
- What qualifies
- Companies worldwide whose own description of what they do matches “security auditing 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 security auditing 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 security auditing firms, and records with no verified work email.
- 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, 36,431 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 between September 6, 2026 and September 14, 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.
Security auditing firms by location
71 lists · largest firstEvery Security auditing firms list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Security auditing firms based in the United States3,309
- Security auditing firms based in the United Kingdom863
- Security auditing firms based in India683
- Security auditing firms based in France463
- Security auditing firms based in Canada447
- Security auditing firms based in Australia440
- Security auditing firms based in Brazil372
- Security auditing firms based in Germany337
- Security auditing firms based in the Netherlands282
- Security auditing firms based in Spain251
- Security auditing firms based in South Africa153
- Security auditing firms based in Italy142
- Security auditing firms based in Switzerland137
- Security auditing firms based in Mexico134
- Security auditing firms based in Poland117
- Security auditing firms based in Israel115
- Security auditing firms based in Belgium110
- Security auditing firms based in the United Arab Emirates103
- Security auditing firms based in Sweden94
- Security auditing firms based in Türkiye83
- Security auditing firms based in Argentina75
- Security auditing firms based in Chile61
- Security auditing firms based in New Zealand56
- Security auditing firms based in Colombia49
- Security auditing firms based in Indonesia48
- Security auditing firms based in Austria37
- Security auditing firms based in Saudi Arabia36
- Security auditing firms based in Romania33
- Security auditing firms based in Ireland32
- Security auditing firms based in Hungary31
- Security auditing firms based in Ecuador30
- Security auditing firms based in Kenya29
- Security auditing firms based in Portugal28
- Security auditing firms based in Malaysia26
- Security auditing firms based in Ukraine26
Cities
- Security auditing firms based in Sydney, Australia101
- Security auditing firms based in Melbourne, Australia82
- Security auditing firms based in London, United Kingdom78
- Security auditing firms based in Toronto, Canada75
- Security auditing firms based in New York, United States62
- Security auditing firms based in Hyderabad, India54
- Security auditing firms based in Paris, France54
- Security auditing firms based in Bangalore, India53
- Security auditing firms based in Atlanta, United States49
- Security auditing firms based in Mumbai, India49
- Security auditing firms based in Pune, India49
- Security auditing firms based in Sao Paulo, Brazil47
- Security auditing firms based in Tampa, United States46
- Security auditing firms based in Austin, United States45
- Security auditing firms based in Houston, United States44
- Security auditing firms based in Bengaluru, India38
- Security auditing firms based in Chennai, India36
- Security auditing firms based in San Diego, United States36
- Security auditing firms based in Brisbane, Australia35
- Security auditing firms based in Washington, United States35
- Security auditing firms based in Ahmedabad, India33
- Security auditing firms based in Arlington, United States33
- Security auditing firms based in Charlotte, United States32
- Security auditing firms based in Los Angeles, United States32
- Security auditing firms based in San Francisco, United States32
- Security auditing firms based in Chicago, United States31
- Security auditing firms based in Dallas, United States31
- Security auditing firms based in Miami, United States31
- Security auditing firms based in Seattle, United States31
- Security auditing firms based in Ottawa, Canada30
- Security auditing firms based in Vancouver, Canada30
- Security auditing firms based in Calgary, Canada27
- Security auditing firms based in Las Vegas, United States27
- Security auditing firms based in Canberra, Australia26
- Security auditing firms based in Columbia, United States26
- Security auditing firms based in Denver, United States26
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 security auditing 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 security auditing firms are there worldwide?
RevenueBase identified 9,232 security auditing firms worldwide 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?
OPTIV, headquartered in Leawood, tops this list with the largest team on record.
Which country has the most security auditing firms?
The United States leads with 3,309 companies, followed by the United Kingdom (863) and India (683). Every security auditing firms list by country and city is linked on this page.
Which city has the most security auditing firms?
London leads with 337 headquartered companies, followed by Sao Paulo (145) and Paris (139).
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 36,431 verified decision-maker contacts tracked across these 9,232 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled from the company graph between September 6, 2026 and September 14, 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.