Company lists · Data refreshed August 2026

Top 25 Cloud security software companies based in the United Kingdom

RevenueBase identified 169 cloud security software companies headquartered in the United Kingdom as of August 2026 and tracks 8,212 professional contacts across them, including 4,298 with verified work emails and 1,485 with mobile numbers. London is the largest hub.

This list covers cloud security software 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
169Companies
8,212Contacts tracked
4,298Verified emails
1,485Mobile numbers
Explore this list → Free signup · no credit card · 500 free credits

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

Ranked by team size
Top 25 of 169 cloud security software 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 security software 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 evidenceAbingdon, United Kingdom5,001-10,0004,963 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
2Indirect evidenceLondon, United Kingdom501-1,000799 contacts →

Indirect evidence

“Netwrix secures the foundation of modern business: data and identity.”

Source: RevenueBase Database · checked Aug 31, 2026
3Partial evidenceGlasgow, United Kingdom201-500422 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
4Indirect evidenceEdinburgh, United Kingdom201-500292 contacts →

Indirect evidence

“At Quorum Cyber, we're on a mission to help good people win.”

Source: RevenueBase Database · checked Aug 31, 2026
5Partial evidenceCheltenham, United Kingdom51-200234 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
6Strong evidenceLondon, United Kingdom201-500182 contacts →

Strong evidence

“Synacor is a cloud-based software and services company headquartered in Buffalo, New York with offices across the globe.”

Source: RevenueBase Database · checked Aug 31, 2026
7Strong evidenceAshburton, United Kingdom51-200103 contacts →

Strong evidence

“We’re Grey Matter, a software reseller and cloud service provider.”

Source: RevenueBase Database · checked Aug 31, 2026
8Indirect evidenceBlandford, United Kingdom51-20068 contacts →

Indirect evidence

“The organisations that run our world face relentless complexity and evolving threats.”

Source: RevenueBase Database · checked Aug 31, 2026
9Indirect evidenceBournemouth, United Kingdom51-20066 contacts →

Indirect evidence

“We help businesses and individuals stay protected in an increasingly complex digital world.”

Source: RevenueBase Database · checked Aug 31, 2026
10Indirect evidenceAscot, United Kingdom1,001-5,00059 contacts →

Indirect 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
11Indirect evidenceCambridge, United Kingdom1,001-5,00057 contacts →

Indirect evidence

“SentinelOne, an autonomous cybersecurity platform company, has completed the acquisition of Attivo Networks.”

Source: RevenueBase Database · checked Aug 31, 2026
12Indirect evidenceLondon, United Kingdom51-20054 contacts →

Indirect evidence

“Cloudmark was acquired by Proofpoint.”

Source: RevenueBase Database · checked Aug 31, 2026
13Indirect evidenceLondon, United Kingdom201-50052 contacts →

Indirect evidence

“Tessian was acquired by Proofpoint.”

Source: RevenueBase Database · checked Aug 31, 2026
14Indirect evidenceSheffield, United Kingdom51-20046 contacts →

Indirect evidence

“Get to know etiCloud - Delivering tomorrow's technology, today.”

Source: RevenueBase Database · checked Aug 31, 2026
15Partial evidenceCheltenham, United Kingdom51-20041 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
16Partial evidenceManchester, United Kingdom11-5035 contacts →

Partial evidence

“Secure, compliant and resilient Cloud IT for legal, accounting, financial and professional service companies IT Farm helps you focus on the sustainability and long term growth of…”

Source: RevenueBase Database · checked Aug 31, 2026
17Partial evidenceStevenage, United Kingdom51-20032 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
18Partial evidenceLondon, United Kingdom51-20031 contacts →

Partial evidence

“OnApp makes cloud fast, easy & profitable for Telcos, MSPs & other cloud service providers.”

Source: RevenueBase Database · checked Aug 31, 2026
19Indirect evidenceBerkshire, United Kingdom201-50019 contacts →

Indirect evidence

“Why Clearswift?”

Source: RevenueBase Database · checked Aug 31, 2026
20Indirect evidenceCheltenham, United Kingdom11-5018 contacts →

Indirect evidence

“Hexiosec is the new name for Red Maple Technologies.”

Source: RevenueBase Database · checked Aug 31, 2026
21Partial evidenceWinchester, United Kingdom11-5018 contacts →

Partial evidence

“QWARE is an award-winning Cloud Solutions and Services provider, with a passion for delivering high-quality cloud-first solutions to businesses worldwide.”

Source: RevenueBase Database · checked Aug 31, 2026
22Strong evidenceChelmsford, United Kingdom201-50018 contacts →

Strong evidence

“Organisation focused on Cloud and Security

Source: RevenueBase Database · checked Aug 31, 2026
23Partial evidenceLondon, United Kingdom11-5017 contacts →

Partial evidence

“CloudFruition is a cloud consulting and professional services company that provides comprehensive solutions to businesses across AWS, Azure, and Google Cloud platforms.”

Source: RevenueBase Database · checked Aug 31, 2026
24Indirect evidenceNewbury, United Kingdom11-5016 contacts →

Indirect evidence

“CyberHive protects the most valued organisations, their people data, and assets, with patented technology that is simple, secure and performant.”

Source: RevenueBase Database · checked Aug 31, 2026
25Indirect evidenceSouthwark, United Kingdom11-5016 contacts →

Indirect evidence

“Award-winning BlockAPT is redefining cybersecurity with an AI-powered, autonomous, self-defending platform built to protect modern digital ecosystems at speed and scale.”

Source: RevenueBase Database · checked Aug 31, 2026

Showing 25 of 169 cloud security software companies based in the United Kingdom

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 4,298 reachable decision-makers.

Free signup · no credit card

View the full list →

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

As of Aug 31, 2026
52.3%Verified-email coverage
18.1%Mobile-number coverage
48.6Average contacts per company
1-10Median size (employees)
43.2%Largest-city concentration · London
Aug 31, 2026Page data refreshed

Companies by employee count

1-10
83
11-50
57
51-200
12
201-500
9
501-1,000
2
1,001-5,000
2
5,001-10,000
1

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 security software 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 security software 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 security software 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 security software 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, 4,298 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 security software companies by metro

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 security software 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 security software companies are there based in the United Kingdom?

RevenueBase identified 169 cloud security software 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 security software companies?

London leads with 73 headquartered companies, followed by Manchester (7) and Cheltenham (4).

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 4,298 verified decision-maker contacts tracked across these 169 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.

Ready to reach these companies? Verified emails and direct dials for all 169 cloud security software companies based in the United Kingdom. Start with a free account, no credit card.

Download this list →

Related lists

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.