Company lists · Data refreshed November 2026

Top 25 Managed security companies based in the United Kingdom

RevenueBase identified 1,701 company matches for managed security companies associated with the United Kingdom as of November 2026 and tracks 32,638 professional contacts across them, including 7,296 with verified work emails. London is the largest hub.

This list covers company matches for managed security companies 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 November 5, 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 Nov 5, 2026 How this list was built
1,701Companies
32,638Contacts tracked
7,296Verified emails
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The 25 largest managed security companies based in the United Kingdom

Ranked by team size
Top 25 of 1,701 company matches for managed security companies based in the United Kingdom, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 5, 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.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchAbingdon, United KingdomHQ recorded Nov 5, 20265,001-10,0005,283 contacts →

Exact match

“Sophos, a global cybersecurity leader, defends more than organizations worldwide with Sophos Fusion, the industry's first and most complete AI-native cybersecurity defense system…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
2Exact matchLondon, United KingdomHQ recorded Nov 5, 20261,001-5,0001,029 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 · Nov 5, 2026 · View company records in RevenueBase
3Exact matchLondon, United KingdomHQ recorded Nov 5, 20261,001-5,000981 contacts →

Exact match

“Corps Security - experts in security with social value Built on over 165 years of experience, Corps provides specialist security services, across the UK, to ensure the safety of…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
4Exact matchUnited KingdomHQ recorded Nov 5, 20261,001-5,000820 contacts →

Exact match

“Ranked in the top 1% of UK security companies, as approved by the Security Industry Authority, SecuriGroup is an award-winning security company, specialising in the provision of…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
5Exact matchLondon, United KingdomHQ recorded Nov 5, 20261,001-5,000458 contacts →

Exact match

“Ward is an award winning, privately owned business, providing bespoke risk and security solutions including protective security personnel, explosive search dogs, narcotic search…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
6Exact matchSwindon, United KingdomHQ recorded Nov 5, 2026501-1,000413 contacts →

Exact match

“SSGC is a leading innovator in the Manned Guarding industry, specialising in the application of new technology to improve the performance of its Management team, deployed staff…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
7Exact matchEdinburgh, United KingdomHQ recorded Nov 5, 2026201-500276 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
8Exact matchShirley, United KingdomHQ recorded Nov 5, 20261,001-5,000246 contacts →

Exact match

“MAN Commercial is a leading security company and Training Academy based in Solihull, West Midlands.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
9Exact matchNewcastle, United KingdomHQ recorded Nov 5, 20261,001-5,000239 contacts →

Exact match

“Phoenix Security is part of the Danieli Holdings Group of companies and also includes one of the UK’s leading Stewarding, CCTV and Manned Guarding companies, Phoenix Eye.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
10Exact matchDublin 8, United KingdomHQ recorded Nov 5, 202651-200184 contacts →

Exact match

“Qualcom provides ultra secure managed IT services using a security first ethos which maximises IT uptime and ensures that data is protected and accessible 24/7.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
11Exact matchLeeds, United KingdomHQ recorded Nov 5, 20261,001-5,000184 contacts →

Exact match

“Established in 1978, Bridgegate Security is proud to be one of the UK’s largest independent security contractors.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
12Exact matchMiddx, United KingdomHQ recorded Nov 5, 2026201-500183 contacts →

Exact match

“We are able to supply a one stop security service for all types of security requirement.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
13Exact matchMarlow, United KingdomHQ recorded Nov 5, 202651-200182 contacts →

Exact match

“24 x 7 Cloud Service Provider & Managed Security Service Provider delivering technology transformation.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
14Exact matchEnfield, United KingdomHQ recorded Nov 5, 2026501-1,000171 contacts →

Exact match

“We are GUK.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
15Exact matchSwindon, United KingdomHQ recorded Nov 5, 202651-200171 contacts →

Exact match

“One of the largest independent security companies in the UK.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
16Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-200165 contacts →

Exact match

“The Keyholding Company are a tech-enabled mobile security services company, specialising in alarm response, mobile patrols, locks and unlocks, emergency and temporary guarding…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
17Exact matchThatcham, United KingdomHQ recorded Nov 5, 202651-200161 contacts →

Exact match

“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…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
18Exact matchNewton-le-willows, United KingdomHQ recorded Nov 5, 20265,001-10,000151 contacts →

Exact match

“About Kingdom Security Established in March 1993, Kingdom Security is a leading UK security provider delivering professional, fully licensed security services nationwide.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
19Exact matchLondon, United KingdomHQ recorded Nov 5, 20261,001-5,000151 contacts →

Exact match

“Vigilant Security provides a range of services including keyholding, corporate security, event security, mobile patrols as well as specialist services throughout the UK.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
20Exact matchPortsmouth, United KingdomHQ recorded Nov 5, 2026201-500135 contacts →

Exact match

“Vespasian Security was formed in February 2006.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
21Exact matchLondon, United KingdomHQ recorded Nov 5, 20261,001-5,000134 contacts →

Exact match

“CGS is a dynamic and professional FM company, specialising in customer focussed security provisions and cleaning specialists.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
22Exact matchLondon, United KingdomHQ recorded Nov 5, 202611-50127 contacts →

Exact match

“At Secon, we empower our clients to reach their full potential by taking the stress out of cyber security.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
23Exact matchHornchurch, United KingdomHQ recorded Nov 5, 2026501-1,000124 contacts →

Exact match

“We are a well-established company that supplies specialist Close Protection, Door Supervisor services to Private Individuals, Visiting Royal Families, Government Officials…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
24Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-200108 contacts →

Exact match

“CyberOne is a Microsoft Security Elite Partner and one of only 100 global Microsoft partners recognised with Microsoft-Verified Managed XDR solution status.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
25Exact matchCambridge, United KingdomHQ recorded Nov 5, 202651-200105 contacts →

Exact match

“For over 25 years, Cambridge-based Softwerx has redefined cybersecurity for midmarket organisations with its financially guaranteed 24×7x365 Managed XDR solutions.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase

Showing 25 of 1,701 managed security companies based in the United Kingdom

See the full list, filter by size, metro and specialty, and access 7,296 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Managed security companies based in the United Kingdom at a glance

As of Nov 5, 2026
22.4%Verified-email coverage
19.2Average contacts per company
11-50Median size (employees)
27.6%Largest-city concentration · London
Nov 5, 2026Page data refreshed

Companies by employee count

1-10
606
11-50
573
51-200
351
201-500
93
501-1,000
19
1,001-5,000
19
5,001-10,000
5
10001+
5

Email recency for this list is measured worldwide rather than for United Kingdom, so it is reported there. Company counts and contact totals on this page are exact for United Kingdom, over 1,701 companies.

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 “managed security companies” 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 7,296 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 November 5, 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.

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 “managed security companies”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many managed security companies are there based in the United Kingdom?

RevenueBase identified 1,701 company matches for managed security companies associated with the United Kingdom as of November 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 managed security companies?

London leads with 470 company records, followed by Manchester (61) and Birmingham (47).

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 7,296 professional contacts with verified work emails tracked across these 1,701 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 November 5, 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.