Company lists · Data refreshed September 2026

Top 25 Cybersecurity consultancies based in the United Kingdom

Name: Cybersecurity consultancies based in the United Kingdom
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 24, 2026 4,932 companies tracked

RevenueBase identified 4,932 company matches for cybersecurity consultancies associated with the United Kingdom as of September 2026 and tracks 84,406 professional contacts across them, including 30,915 with verified work emails and 6,583 with mobile numbers. London is the largest hub.

This list covers company matches for cybersecurity consultancies associated with the United Kingdom, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed September 24, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, 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 RevenueBase SmartSearch · Exact Recorded Sep 24, 2026 How this list was built

4,932Companies

84,406Contacts tracked

30,915Verified emails

6,583Mobile numbers

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The 25 largest cybersecurity consultancies based in the United Kingdom

Ranked by team size

Top 25 of 4,932 company matches for cybersecurity consultancies based in the United Kingdom, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 24, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	Sophos	Exact match	Abingdon, United KingdomHQ recorded Sep 24, 2026	5,001-10,000	4,925 contacts →
	Exact match “Sophos is a cybersecurity leader defending organizations globally with an AI-driven platform and expert-led services.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
2	Control Risks	Exact match	London, United KingdomHQ recorded Sep 24, 2026	1,001-5,000	2,972 contacts →
	Exact match “Control Risks is a global specialist risk consultancy that helps to create secure, compliant and resilient organisations.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
3	Darktrace	Exact match	Cambridge, United KingdomHQ recorded Sep 24, 2026	1,001-5,000	2,355 contacts →
	Exact match “Darktrace is a global leader in AI cybersecurity, providing the essential cybersecurity platform to secure organizations today and for an ever-changing future.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
4	Mimecast	Exact match	London, United KingdomHQ recorded Sep 24, 2026	1,001-5,000	2,304 contacts →
	Exact match “organizations.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
5	Hack The BOX	Exact match	Folkestone, United KingdomHQ recorded Sep 24, 2026	n/a	1,975 contacts →
	Exact match “Hack The Box is the leading AI-powered cybersecurity readiness and upskilling platform, trusted by 1,500+ organizations worldwide, including Fortune 500 enterprises, government…” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
6	Noventiq	Exact match	London, United KingdomHQ recorded Sep 24, 2026	5,001-10,000	1,508 contacts →
	Exact match “Noventiq (Noventiq Holdings PLC) is a leading global solutions and services provider in digital transformation and cybersecurity, headquartered in London.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
7	Frazer-Nash Consultancy	Exact match	Leatherhead, United KingdomHQ recorded Sep 24, 2026	1,001-5,000	1,437 contacts →
	Exact match “With offices in the UK and Australia, Frazer-Nash is a leading systems, engineering and technology company.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
8	CIS Security Limited	Exact match	London, United KingdomHQ recorded Sep 24, 2026	1,001-5,000	919 contacts →
	Exact match “CIS Security is an independent security company equipped to help customers to solve the complex challenges in today’s digital, connected and regulated business world.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
9	CTS	Exact match	Manchester, United KingdomHQ recorded Sep 24, 2026	201-500	844 contacts →
	Exact match “We are the largest Google Cloud-only digital consultancy in Europe, and our mission is to change the way technology works for business.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
10	MTI	Exact match	Staines-upon-thames, United KingdomHQ recorded Sep 24, 2026	201-500	764 contacts →
	Exact match “MTI provides award-winning, end-to-end technology solutions and services in cyber security and data centre for over 35 years.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
11	MASS	Exact match	St Neots, United KingdomHQ recorded Sep 24, 2026	201-500	640 contacts →
	Exact match “MASS, part of the Cohort plc group, helps you realise the value of your data.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
12	Dimension Data UKI	Exact match	Fleet, United KingdomHQ recorded Sep 24, 2026	1,001-5,000	540 contacts →
	Exact match “Dimension Data uses the power of technology to help organisations achieve great things.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
13	Securityhq	Exact match	London, United KingdomHQ recorded Sep 24, 2026	501-1,000	502 contacts →
	Exact match “SecurityHQ, a global cybersecurity company pioneering Security Performance Engineering for stronger operational performance and resilience.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
14	Analysys Mason	Exact match	London, United KingdomHQ recorded Sep 24, 2026	201-500	459 contacts →
	Exact match “Analysys Mason is the leading specialist consultancy, creating lasting value in technology-intensive industries, including telecoms, digital infrastructure, software, IT services…” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
15	ACORA	Exact match	Burgess Hill, United KingdomHQ recorded Sep 24, 2026	501-1,000	423 contacts →
	Exact match “We’ve been on a mission to bring together people and technology since the day we were founded over 25 years ago.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
16	Lodge Security	Exact match	Cirencester, United KingdomHQ recorded Sep 24, 2026	1,001-5,000	422 contacts →
	Exact match “Unlike traditional security providers, we're redefining what protection means in today's world.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
17	Trustmarque	Exact match	York, United KingdomHQ recorded Sep 24, 2026	501-1,000	421 contacts →
	Exact match “Trustmarque delivers the value of technology to bring real-life impact.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
18	FSP	Exact match	Reading, United KingdomHQ recorded Sep 24, 2026	201-500	366 contacts →
	Exact match “FSP is a leading consultancy specialising in Data and AI, Cyber Security, Enterprise Cloud and Change Delivery, providing advisory led enterprise transformation delivered through…” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
19	Littlefish	Exact match	Nottingham, United KingdomHQ recorded Sep 24, 2026	201-500	364 contacts →
	Exact match “Littlefish is a multi-award-winning Managed IT Services Provider that continues to grow consistently and significantly through tangibly delivering on our promises of enhanced user…” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
20	Immersive	Exact match	Bristol, United KingdomHQ recorded Sep 24, 2026	201-500	352 contacts →
	Exact match “The leader in people-centric cyber resilience.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
21	S-Rm	Exact match	London, United KingdomHQ recorded Sep 24, 2026	201-500	351 contacts →
	Exact match “S-RM is a global intelligence and cyber security consultancy.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
22	Kings Secure Technologies	Exact match	Bradford, United KingdomHQ recorded Sep 24, 2026	501-1,000	326 contacts →
	Exact match “Kings Secure Technologies (KST) is a high-end, enterprise-level systems integrator.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
23	Reliance Infosystems	Exact match	West End, United KingdomHQ recorded Sep 24, 2026	201-500	326 contacts →
	Exact match “As our name suggests, our customers rely on us in providing suitable technology inputs to support their business goals.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
24	Bridewell	Exact match	Reading, United KingdomHQ recorded Sep 24, 2026	201-500	303 contacts →
	Exact match “Bridewell is the trusted cyber security partner for organisations operating within Critical National Infrastructure (CNI), as well as companies who want the highest standard of…” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase
25	Quorum Cyber	Exact match	Edinburgh, United KingdomHQ recorded Sep 24, 2026	201-500	297 contacts →
	Exact match “At Quorum Cyber, we're on a mission to help good people win.” Recorded in the RevenueBase company graph · Sep 24, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “cybersecurity consultancies”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 25 of 4,932 cybersecurity consultancies based in the United Kingdom

See the full list, filter by size, metro and specialty, and access 30,915 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Cybersecurity consultancies based in the United Kingdom at a glance

As of Sep 24, 2026

36.6%Verified-email coverage

7.8%Mobile-number coverage

17.1Average contacts per company

1-10Median size (employees)

36.3%Largest-city concentration · London

Sep 24, 2026Page data refreshed

Companies by employee count

1-10

3,044

11-50

1,359

51-200

352

201-500

101

501-1,000

1,001-5,000

5,001-10,000

10001+

Freshness & accuracy

How recently the business emails were verified and the company information checked

Email last verified

Median 26.0d

23,1710–30

7,05731–60

44261–90

1990–180

226180+

Company record updated

Median 87.0d

00–30

11,41331–60

40,33461–90

27,40590–180

5,254180+

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies: Company records associated with the United Kingdom whose business descriptions match “cybersecurity consultancies” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch: Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview: The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality: RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
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 displayed company carries at least one verified work email. RevenueBase tracks 30,915 professional contacts with verified work emails across the full matched dataset. 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 24, 2026. Lists refresh periodically as the graph is re-checked.
Record context: Company records and descriptions can change. Check the company's website for its current services and locations.

Cybersecurity consultancies by metro

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “cybersecurity consultancies”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many cybersecurity consultancies are there based in the United Kingdom?

RevenueBase identified 4,932 company matches for cybersecurity consultancies associated with the United Kingdom as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Sophos tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most cybersecurity consultancies?

London leads with 1791 company records, followed by Manchester (143) and Birmingham (71).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 30,915 professional contacts with verified work emails tracked across these 4,932 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 24, 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 SmartSearch, 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.