Company lists · Data refreshed August 2026

Top 25 Cloud infrastructure security companies based in the United Kingdom

Name: Cloud infrastructure security companies based in the United Kingdom
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Aug 31, 2026 226 companies tracked

RevenueBase identified 226 cloud infrastructure security companies headquartered in the United Kingdom as of August 2026 and tracks 8,768 professional contacts across them, including 4,112 with verified work emails and 1,566 with mobile numbers. London is the largest hub.

This list covers cloud infrastructure security companies 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 August 31, 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 RevenueBase Smart Search rating on every row Refreshed Aug 31, 2026 86% judged on-target in blind review

226Companies

8,768Contacts tracked

4,112Verified emails

1,566Mobile numbers

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The 25 largest cloud infrastructure security companies based in the United Kingdom

Ranked by team size

Top 25 of 226 cloud infrastructure security companies based in the United Kingdom, ranked by team size, largest first. Data refreshed Aug 31, 2026. RevenueBase Smart Search rates how each company's information relates to cloud infrastructure security 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.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Sophos	Indirect evidence	Abingdon, United Kingdom	5,001-10,000	4,963 contacts →
	Indirect evidence “Sophos is a cybersecurity leader defending organizations globally with an AI-driven platform and expert-led services.” Source: RevenueBase Database · checked Aug 31, 2026
2	Everfox	Indirect evidence	London, United Kingdom	1,001-5,000	635 contacts →
	Indirect evidence “Everfox delivers trusted connectivity to protect the world's most critical environments, safeguarding the sensitive information behind decision advantage.” Source: RevenueBase Database · checked Aug 31, 2026
3	Iomart	Partial evidence	Glasgow, United Kingdom	201-500	422 contacts →
	Partial evidence “Iomart combines cutting-edge cloud technology with deep industry expertise to help organisations transform with confidence.” Source: RevenueBase Database · checked Aug 31, 2026
4	Quorum Cyber	Indirect evidence	Edinburgh, United Kingdom	201-500	292 contacts →
	Indirect evidence “At Quorum Cyber, we're on a mission to help good people win.” Source: RevenueBase Database · checked Aug 31, 2026
5	Obsidian Security	Partial evidence	Cheltenham, United Kingdom	51-200	234 contacts →
	Partial evidence “Protect your business-critical applications by mitigating threats and reducing risk with Obsidian, the first truly comprehensive security solution for SaaS.” Source: RevenueBase Database · checked Aug 31, 2026
6	Cyberfort	Strong evidence	Thatcham, United Kingdom	51-200	160 contacts →
	Strong evidence “At Cyberfort we are passionate about the cyber security services we deliver for our customers which keeps their people, data, systems and technology infrastructure secure…” Source: RevenueBase Database · checked Aug 31, 2026
7	Bulletproof Cyber Security	Indirect evidence	London, United Kingdom	51-200	118 contacts →
	Indirect evidence “Bulletproof is now part of WorkNest Secure.” Source: RevenueBase Database · checked Aug 31, 2026
8	Appcheck LTD	Partial evidence	Leeds, United Kingdom	51-200	97 contacts →
	Partial evidence “AppCheck is a Complete Enterprise Security Testing Solution that provides up to the minute vulnerability coverage for your entire estate.” Source: RevenueBase Database · checked Aug 31, 2026
9	Virtual IT LTD	Partial evidence	Laindon, United Kingdom	51-200	79 contacts →
	Partial evidence “Virtual IT are a leading provider of cyber-secure cloud and managed IT services in the UK, entrusted by over 700 businesses and schools as their end-to-end technology partner.” Source: RevenueBase Database · checked Aug 31, 2026
10	Brightsolid	Strong evidence	Dundee, United Kingdom	51-200	77 contacts →
	Strong evidence “Brightsolid is expert in all things colocation, cloud and cyber security.” Source: RevenueBase Database · checked Aug 31, 2026
11	CIVO	Partial evidence	London, United Kingdom	51-200	75 contacts →
	Partial evidence “Civo is the Sovereign Cloud and AI platform that frees you to build without limits.” Source: RevenueBase Database · checked Aug 31, 2026
12	Cloudrise	Strong evidence	London, United Kingdom	51-200	69 contacts →
	Strong evidence “Cloudrise, an Exclusive Networks company, is your go-to team for world-class data, network, and cloud security services.” Source: RevenueBase Database · checked Aug 31, 2026
13	Telesoft	Indirect evidence	Blandford, United Kingdom	51-200	68 contacts →
	Indirect evidence “The organisations that run our world face relentless complexity and evolving threats.” Source: RevenueBase Database · checked Aug 31, 2026
14	Intruder	Indirect evidence	London, United Kingdom	51-200	61 contacts →
	Indirect evidence “Intruder was founded in 2015 to help solve the information overload crisis in vulnerability management.” Source: RevenueBase Database · checked Aug 31, 2026
15	Iland 11 11 Systems	Partial evidence	Ascot, United Kingdom	1,001-5,000	59 contacts →
	Partial evidence “11:11 Systems is a managed infrastructure solutions provider that empowers customers to modernize, protect, and manage mission-critical applications and data, leveraging 11:11’s…” Source: RevenueBase Database · checked Aug 31, 2026
16	Coretech Security	Partial evidence	Cheltenham, United Kingdom	51-200	41 contacts →
	Partial evidence “CoreTech is a specialist cyber security company whose people are motivated by the desire to deliver exceptional capabilities coupled with a real sense of mission.” Source: RevenueBase Database · checked Aug 31, 2026
17	Secarma LTD	Indirect evidence	Manchester, United Kingdom	11-50	34 contacts →
	Indirect evidence “Secarma exists to keep the world safe.” Source: RevenueBase Database · checked Aug 31, 2026
18	FLOW	Partial evidence	Hemel Hempstead, United Kingdom	11-50	33 contacts →
	Partial evidence “Our expert team provide secure datacentre, network and cloud native solutions as well as industry leading managed services.” Source: RevenueBase Database · checked Aug 31, 2026
19	Cased Dimensions	Indirect evidence	Belfast, United Kingdom	11-50	33 contacts →
	Indirect evidence “Secure IT by Design.” Source: RevenueBase Database · checked Aug 31, 2026
20	defense.com	Partial evidence	Stevenage, United Kingdom	51-200	32 contacts →
	Partial evidence “Defense.com is transforming the way businesses manage cyber security by allowing them to easily identify, prioritise and remediate threats.” Source: RevenueBase Database · checked Aug 31, 2026
21	Omnicyber Security	Partial evidence	Solihull, United Kingdom	11-50	31 contacts →
	Partial evidence “SPECIALISTS IN IT SECURITY AND COMPLIANCE Our goal is to help customers define, develop and implement information security and compliance services, no matter what stage of the…” Source: RevenueBase Database · checked Aug 31, 2026
22	Dnssense	Partial evidence	London, United Kingdom	51-200	30 contacts →
	Partial evidence “DNSSense, positioned under Noventiq during 2024–2025, completed a 100% local-ownership restructuring in 2025 and evolved into a Turkey-based, R&D-driven DNS security company.” Source: RevenueBase Database · checked Aug 31, 2026
23	AMR Cybersecurity	Partial evidence	Cheltenham, United Kingdom	11-50	23 contacts →
	Partial evidence “AMR CyberSecurity delivers next generation cyber security services to assist organisations across a wide variety of sectors in understanding potential threats and effectively…” Source: RevenueBase Database · checked Aug 31, 2026
24	Vambrace Cybersecurity	Indirect evidence	Leeds, United Kingdom	11-50	23 contacts →
	Indirect evidence “Whatever you supply, design, build, manufacture, or grow, its excelling at it that has got your business to where it is today.” Source: RevenueBase Database · checked Aug 31, 2026
25	CYPRO	Indirect evidence	London, United Kingdom	11-50	22 contacts →
	Indirect evidence “Secure.” Source: RevenueBase Database · checked Aug 31, 2026

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: cloud infrastructure security companies. 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 cloud infrastructure security companies.
Partial evidence: Its own public description names part of cloud infrastructure security companies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name cloud infrastructure security companies. 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 226 cloud infrastructure security companies based in the United Kingdom

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Cloud infrastructure security companies based in the United Kingdom at a glance

As of Aug 31, 2026

46.9%Verified-email coverage

17.9%Mobile-number coverage

38.8Average contacts per company

11-50Median size (employees)

45.6%Largest-city concentration · London

Aug 31, 2026Page data refreshed

Companies by employee count

1-10

111

11-50

51-200

201-500

501-1,000

1,001-5,000

5,001-10,000

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 cloud infrastructure security 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.
What qualifies: Companies headquartered in the United Kingdom whose own description of what they do matches “cloud infrastructure security 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 cloud infrastructure security 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 cloud infrastructure security companies, 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, 4,112 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 August 31, 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.

Cloud infrastructure security companies by metro

Cloud infrastructure security companies in London103

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 cloud infrastructure security 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 cloud infrastructure security companies are there based in the United Kingdom?

RevenueBase identified 226 cloud infrastructure security companies headquartered in the United Kingdom as of August 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 cloud infrastructure security companies?

London leads with 103 headquartered companies, followed by Manchester (10) and Cheltenham (6).

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 4,112 verified decision-maker contacts tracked across these 226 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on August 31, 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.