Company lists · Data refreshed September 2026

Top 25 Cyber consultancies based in the United Kingdom

RevenueBase identified 4,605 cyber consultancies headquartered in the United Kingdom as of September 2026 and tracks 58,696 professional contacts across them, including 19,910 with verified work emails and 4,243 with mobile numbers. London is the largest hub.

This list covers cyber consultancies headquartered in the United Kingdom, 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 24, 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.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 24, 2026 86% judged on-target in blind review
4,605Companies
58,696Contacts tracked
19,910Verified emails
4,243Mobile numbers
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The 25 largest cyber consultancies based in the United Kingdom

Ranked by team size
Top 25 of 4,605 cyber consultancies based in the United Kingdom, ranked by team size, largest first. Data refreshed Sep 24, 2026. RevenueBase Smart Search rates how each company's information relates to cyber consultancies: 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 evidenceAbingdon, United KingdomHQ checked Sep 24, 20265,001-10,0004,925 contacts →

Indirect evidence

“Sophos is a cybersecurity leader defending organizations globally with an AI-driven platform and expert-led services.”

Source: RevenueBase Database · checked Sep 24, 2026
2Partial evidenceStaines-upon-thames, United KingdomHQ checked Sep 24, 2026201-500764 contacts →

Partial evidence

“MTI provides award-winning, end-to-end technology solutions and services in cyber security and data centre for over 35 years.”

Source: RevenueBase Database · checked Sep 24, 2026
3Indirect evidenceGateshead, United KingdomHQ checked Sep 24, 2026201-500748 contacts →

Indirect evidence

“TSG: The Technology Partner for Ambitious Businesses We're not a reseller.”

Source: RevenueBase Database · checked Sep 24, 2026
4Indirect evidenceSt Neots, United KingdomHQ checked Sep 24, 2026201-500640 contacts →

Indirect evidence

“MASS, part of the Cohort plc group, helps you realise the value of your data.”

Source: RevenueBase Database · checked Sep 24, 2026
5Indirect evidenceLondon, United KingdomHQ checked Sep 24, 2026501-1,000502 contacts →

Indirect evidence

“SecurityHQ, a global cybersecurity company pioneering Security Performance Engineering for stronger operational performance and resilience.”

Source: RevenueBase Database · checked Sep 24, 2026
6Indirect evidenceLondon, United KingdomHQ checked Sep 24, 2026201-500459 contacts →

Indirect evidence

“Analysys Mason is the leading specialist consultancy, creating lasting value in technology-intensive industries, including telecoms, digital infrastructure, software, IT services…”

Source: RevenueBase Database · checked Sep 24, 2026
7Indirect evidenceYork, United KingdomHQ checked Sep 24, 2026501-1,000421 contacts →

Indirect evidence

“Trustmarque delivers the value of technology to bring real-life impact.”

Source: RevenueBase Database · checked Sep 24, 2026
8Partial evidenceReading, United KingdomHQ checked Sep 24, 2026201-500366 contacts →

Partial evidence

“FSP is a leading consultancy specialising in Data and AI, Cyber Security, Enterprise Cloud and Change Delivery, providing advisory led enterprise transformation delivered through…”

Source: RevenueBase Database · checked Sep 24, 2026
9Indirect evidenceNottingham, United KingdomHQ checked Sep 24, 2026201-500364 contacts →

Indirect evidence

“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…”

Source: RevenueBase Database · checked Sep 24, 2026
10Partial evidenceLondon, United KingdomHQ checked Sep 24, 2026201-500351 contacts →

Partial evidence

“S-RM is a global intelligence and cyber security consultancy.”

Source: RevenueBase Database · checked Sep 24, 2026
11Indirect evidenceWest End, United KingdomHQ checked Sep 24, 2026201-500326 contacts →

Indirect evidence

“As our name suggests, our customers rely on us in providing suitable technology inputs to support their business goals.”

Source: RevenueBase Database · checked Sep 24, 2026
12Partial evidenceReading, United KingdomHQ checked Sep 24, 2026201-500303 contacts →

Partial evidence

“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…”

Source: RevenueBase Database · checked Sep 24, 2026
13Indirect evidenceHemel Hempstead, United KingdomHQ checked Sep 24, 2026201-500295 contacts →

Indirect evidence

“boxxe is a leading provider of hardware, software, and managed IT services for public and private sector organisations.”

Source: RevenueBase Database · checked Sep 24, 2026
14Indirect evidenceGateshead, United KingdomHQ checked Sep 24, 2026201-500266 contacts →

Indirect evidence

“Welcome to Aspire Technology Solutions!”

Source: RevenueBase Database · checked Sep 24, 2026
15Indirect evidenceLeeds, United KingdomHQ checked Sep 24, 2026201-500260 contacts →

Indirect evidence

“We are a global boutique, specializing exclusively in the convergence of identity-driven security and networking.”

Source: RevenueBase Database · checked Sep 24, 2026
16Partial evidenceLiverpool, United KingdomHQ checked Sep 24, 2026201-500257 contacts →

Partial evidence

“ARO is an award-winning IT Services and Solutions provider with almost 30 years of expertise in Cloud, Cyber Security, IT Collaboration, Data Centre Services, and Sustainability.”

Source: RevenueBase Database · checked Sep 24, 2026
17Indirect evidenceGreenham, United KingdomHQ checked Sep 24, 2026201-500243 contacts →

Indirect evidence

“Roc Technologies delivers transformational IT solutions to public and private sector organisations across the UK.”

Source: RevenueBase Database · checked Sep 24, 2026
18Partial evidenceLondon, United KingdomHQ checked Sep 24, 2026201-500242 contacts →

Partial evidence

“Obrela Security Industries is a global provider of cyber security services.”

Source: RevenueBase Database · checked Sep 24, 2026
19Indirect evidenceDurham, United KingdomHQ checked Sep 24, 2026201-500215 contacts →

Indirect evidence

“We are an IT business with a difference.”

Source: RevenueBase Database · checked Sep 24, 2026
20Indirect evidenceLondon, United KingdomHQ checked Sep 24, 2026201-500211 contacts →

Indirect evidence

“Netcraft provides powerful phishing detection, cybercrime disruption and website takedown solutions to the world's largest organizations”

Source: RevenueBase Database · checked Sep 24, 2026
21Indirect evidencePencoed, United KingdomHQ checked Sep 24, 202651-200211 contacts →

Indirect evidence

“Technology services for the future.”

Source: RevenueBase Database · checked Sep 24, 2026
22Partial evidenceNr Cardiff, United KingdomHQ checked Sep 24, 2026n/a208 contacts →

Partial evidence

“Helping UK businesses reduce IT downtime, strengthen cyber security and adopt AI safely, without the cost and complexity of managing IT in-house.”

Source: RevenueBase Database · checked Sep 24, 2026
23Indirect evidenceLisburn, United KingdomHQ checked Sep 24, 202651-200205 contacts →

Indirect evidence

“Unlock the full potential of your business with digital solutions built for you and with you.”

Source: RevenueBase Database · checked Sep 24, 2026
24Indirect evidenceLondon, United KingdomHQ checked Sep 24, 2026201-500203 contacts →

Indirect evidence

“Established in 2006, FluidOne is an award-winning provider of secure Connected Cloud Solutions with a £110m turnover and consistently one of the highest Net Promoter Scores (NPS)…”

Source: RevenueBase Database · checked Sep 24, 2026
25Partial evidenceLondon, United KingdomHQ checked Sep 24, 2026201-500190 contacts →

Partial evidence

“Intragen is a cyber security business focused on managed Identity solutions and services.”

Source: RevenueBase Database · checked Sep 24, 2026

Showing 25 of 4,605 cyber consultancies based in the United Kingdom

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Cyber consultancies based in the United Kingdom at a glance

As of Sep 24, 2026
33.9%Verified-email coverage
7.2%Mobile-number coverage
12.7Average contacts per company
1-10Median size (employees)
34.8%Largest-city concentration · London
Sep 24, 2026Page data refreshed

Companies by employee count

1-10
3,076
11-50
1,152
51-200
265
201-500
61
501-1,000
14
1,001-5,000
13
5,001-10,000
6
10001+
3

Freshness & accuracy

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

Email last verified

Median 26.0d

Company record updated

Median 88.0d

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 cyber consultancies, 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 Kingdom whose own description of what they do matches “cyber consultancies”. 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 cyber consultancies), 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 cyber consultancies, and records with no verified work email. Companies headquartered outside United Kingdom 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, 19,910 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 24, 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.

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 cyber consultancies, 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 cyber consultancies are there based in the United Kingdom?

RevenueBase identified 4,605 cyber consultancies headquartered in the United Kingdom 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?

Sophos, headquartered in Abingdon, tops this list with the largest team on record.

Which city has the most cyber consultancies?

London leads with 1601 headquartered companies, followed by Manchester (131) and Birmingham (69).

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 19,910 verified decision-maker contacts tracked across these 4,605 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 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 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.