Company lists · Data refreshed September 2026

Top 25 Iso 27001 information security audit companies worldwide

RevenueBase identified 2,979 iso 27001 information security audit companies worldwide as of September 2026 and tracks 41,799 professional contacts across them, including 13,259 with verified work emails. The United Kingdom is the largest market and London the largest hub.

This list covers iso 27001 information security audit companies 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 28, 2026. Country and city lists for iso 27001 information security audit companies 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.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 28, 2026 86% judged on-target in blind review
2,979Companies
41,799Contacts tracked
13,259Verified emails
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The 25 largest iso 27001 information security audit companies worldwide

Ranked by team size
Top 25 of 2,979 iso 27001 information security audit companies worldwide, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to iso 27001 information security audit companies: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceHøvik, NorwayHQ checked Sep 28, 202610001+15,983 contacts →

Indirect evidence

“DNV is the independent expert in risk management and assurance, operating in more than 100 countries.”

Source: RevenueBase Database · checked Sep 28, 2026
2Indirect evidenceFrankfurt Am Main, GermanyHQ checked Sep 28, 20261,001-5,0001,424 contacts →

Indirect evidence

“DQS – Leveraging Quality, Driving Success.”

Source: RevenueBase Database · checked Sep 28, 2026
3Indirect evidenceTampa, FL, United StatesHQ checked Sep 28, 2026501-1,000798 contacts →

Indirect evidence

“A-LIGN is the leading provider of high-quality, efficient cybersecurity compliance programs.”

Source: RevenueBase Database · checked Sep 28, 2026
4Partial evidenceLondon, United KingdomHQ checked Sep 28, 2026n/a705 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 28, 2026
5Indirect evidenceMontreal, QC, CanadaHQ checked Sep 28, 202651-200437 contacts →

Indirect evidence

“PECB is a global leader in certification, committed to fostering digital trust through education, certification, and certificate programs across various disciplines.”

Source: RevenueBase Database · checked Sep 28, 2026
6Strong evidenceNavi Mumbai, IndiaHQ checked Sep 28, 2026201-500400 contacts →

Strong evidence

“qSEAp is a CERT-IN empanelled, ISO 27001, SOC-2 Type2 and ISO 9001 certified Infosec organization founded in 2011 with a mission to deliver quality products, superior solutions…”

Source: RevenueBase Database · checked Sep 28, 2026
7Indirect evidenceKatowice, PolandHQ checked Sep 28, 2026201-500192 contacts →

Indirect evidence

“DAGMA Bezpieczeństwo IT to firma z 40-letnim doświadczeniem, specjalizująca się w cyberbezpieczeństwie.”

Source: RevenueBase Database · checked Sep 28, 2026
8Partial evidenceMunich, GermanyHQ checked Sep 28, 2026201-500189 contacts →

Partial evidence

“DataGuard, the European leader in security and compliance software, is trusted by more than organizations across 50+ countries.”

Source: RevenueBase Database · checked Sep 28, 2026
9Indirect evidenceCork - London - New York City - Bucharest - Krakow - Belfast, IrelandHQ checked Sep 28, 202651-200189 contacts →

Indirect evidence

“At Smarttech247 we help global companies defend against cyber crime and protect their operations.”

Source: RevenueBase Database · checked Sep 28, 2026
10Indirect evidenceLondon, United KingdomHQ checked Sep 28, 2026n/a186 contacts →

Indirect evidence

“IT support for businesses in London.”

Source: RevenueBase Database · checked Sep 28, 2026
11Strong evidenceNavi Mumbai, IndiaHQ checked Sep 28, 202651-200181 contacts →

Strong evidence

“QRC Assurance and Solutions has been a forerunner on the cybersecurity front, empanelled with CERT-in, certified to provide PCI DSS QSA, PA QSA, PCI 3DS, PCI SSF, ISO 27001, ISO…”

Source: RevenueBase Database · checked Sep 28, 2026
12Strong evidenceTampa, FL, United StatesHQ checked Sep 28, 2026201-500174 contacts →

Strong evidence

“Insight Assurance is a security and compliance firm trusted by more than 1,500 organizations for their SOC 1, SOC 2, SOC 3, PCI DSS, ISO 27001, ISO 27017/27018, ISO 27701, ISO…”

Source: RevenueBase Database · checked Sep 28, 2026
13Indirect evidenceGuadalajara, MexicoHQ checked Sep 28, 202651-200174 contacts →

Indirect evidence

“Somos una firma con reconocimiento internacional que ofrece servicios de certificación, capacitación y evaluación de la conformidad en diferentes estándares nacionales e…”

Source: RevenueBase Database · checked Sep 28, 2026
14Indirect evidenceChantilly, VA, United StatesHQ checked Sep 28, 20261,001-5,000170 contacts →

Indirect evidence

“Trusted By 2,880+ World-Class Brands And Organizations Of All Sizes…!”

Source: RevenueBase Database · checked Sep 28, 2026
15Strong evidenceHouston, TX, United StatesHQ checked Sep 28, 202651-200167 contacts →

Strong evidence

“ValueMentor is a global information security consulting & services company that delivers real results to global business in maximizing cybersecurity.”

Source: RevenueBase Database · checked Sep 28, 2026
16Strong evidenceComuna 15, ArgentinaHQ checked Sep 28, 202651-200146 contacts →

Strong evidence

“It is led by a group of information security specialists with extensive experience in large local and international companies, whose professional development has begun in one of…”

Source: RevenueBase Database · checked Sep 28, 2026
17Indirect evidenceLas Rozas De Madrid, SpainHQ checked Sep 28, 202651-200145 contacts →

Indirect evidence

“Secure & IT es una empresa especializada en seguridad de la información que trabaja en cinco líneas: compliance, procesos y gobierno IT, sistemas y seguridad IT, seguridad…”

Source: RevenueBase Database · checked Sep 28, 2026
18Strong evidenceNashville, TN, United StatesHQ checked Sep 28, 202651-200139 contacts →

Strong evidence

“KirkpatrickPrice is a licensed information security CPA firm, a PCI QSA, and a HITRUST CSF Assessor, providing assurance services to over clients worldwide.”

Source: RevenueBase Database · checked Sep 28, 2026
19Partial evidenceWest Malling, United KingdomHQ checked Sep 28, 2026201-500138 contacts →

Partial evidence

“Amtivo Group provides expert certification services for ISO standards, as well as training and related services.”

Source: RevenueBase Database · checked Sep 28, 2026
20Indirect evidenceNeu-isenburg, GermanyHQ checked Sep 28, 202651-200130 contacts →

Indirect evidence

“Die usd AG schützt Unternehmen vor Hackern und Kriminellen.”

Source: RevenueBase Database · checked Sep 28, 2026
21Partial evidenceNorwich, United KingdomHQ checked Sep 28, 202651-200115 contacts →

Partial evidence

“We believe in keeping ISO certification simple, so that's exactly what we do.”

Source: RevenueBase Database · checked Sep 28, 2026
22Indirect evidencePatos De Minas, BrazilHQ checked Sep 28, 202651-200115 contacts →

Indirect evidence

“We were born from a dream of being a humane company, with great expertise and boldness in being a reference in our services.”

Source: RevenueBase Database · checked Sep 28, 2026
23Strong evidenceEssen, GermanyHQ checked Sep 28, 202651-200111 contacts →

Strong evidence

“TÜV Informationstechnik GmbH (headquartered in Essen, Germany) is a renowned IT security service provider and an independent testing institute and laboratory for IT security and…”

Source: RevenueBase Database · checked Sep 28, 2026
24Strong evidenceBogotá, ColombiaHQ checked Sep 28, 202651-200111 contacts →

Strong evidence

“B-SECURE provides information security services and technologies that enable organizations to improve their security posture, minimize risk levels and simplify compliance of laws…”

Source: RevenueBase Database · checked Sep 28, 2026
25Strong evidenceParis, FranceHQ checked Sep 28, 202651-200111 contacts →

Strong evidence

“Our services : Penetration tests and Security Audits, Gap Analysis and PCI DSS Certification, CERT-XMCO (vulnerability watch, Cyber Survellance/Threat Intelligence, Forensics).”

Source: RevenueBase Database · checked Sep 28, 2026

Showing 25 of 2,979 iso 27001 information security audit companies worldwide

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Iso 27001 information security audit companies worldwide at a glance

As of Sep 28, 2026
31.7%Verified-email coverage
14.0Average contacts per company
1-10Median size (employees)
2.0%Largest-city concentration · London
Sep 28, 2026Page data refreshed

Companies by employee count

1-10
1,917
11-50
799
51-200
195
201-500
40
501-1,000
8
1,001-5,000
4
5,001-10,000
2
10001+
2

Email recency is reported on each country list linked below.

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 iso 27001 information security audit companies, 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
Every country. Country and city lists for iso 27001 information security audit companies are linked below.
What qualifies
Companies worldwide whose own description of what they do matches “iso 27001 information security audit companies”. 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 iso 27001 information security audit companies), 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 iso 27001 information security audit companies, 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, 13,259 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 28, 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.

Iso 27001 information security audit companies by location

18 lists · largest first

Every Iso 27001 information security audit companies list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

Cities

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 iso 27001 information security audit companies, 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 iso 27001 information security audit companies are there worldwide?

RevenueBase identified 2,979 iso 27001 information security audit companies 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?

DNV, headquartered in Oslo, tops this list with the largest team on record.

Which country has the most iso 27001 information security audit companies?

The United Kingdom leads with 278 companies, followed by India (268) and the United States (206). Every iso 27001 information security audit companies list by country and city is linked on this page.

Which city has the most iso 27001 information security audit companies?

London leads with 60 headquartered companies, followed by Istanbul (24) and Paris (23).

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 13,259 verified decision-maker contacts tracked across these 2,979 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 28, 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.