Company lists · Data refreshed September 2026

Top 25 Security consultancies based in the United Kingdom

RevenueBase identified 5,888 security consultancies headquartered in the United Kingdom as of September 2026 and tracks 159,294 professional contacts across them, including 21,044 with verified work emails. London is the largest hub.

This list covers security 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 21, 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 21, 2026 86% judged on-target in blind review
5,888Companies
159,294Contacts tracked
21,044Verified emails
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The 25 largest security consultancies based in the United Kingdom

Ranked by team size
Top 25 of 5,888 security consultancies based in the United Kingdom, ranked by team size, largest first. Data refreshed Sep 21, 2026. RevenueBase Smart Search rates how each company's information relates to security 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
1Partial evidenceLondon, United KingdomHQ checked Sep 21, 202610001+79,699 contacts →

Partial evidence

“G4S is a leading security and facility services company that provides proactive security services and cutting-edge smart technology to deliver tailored, integrated security…”

Source: RevenueBase Database · checked Sep 21, 2026
2Indirect evidenceStaines, United KingdomHQ checked Sep 21, 202610001+6,169 contacts →

Indirect evidence

“Making the world a safer place.”

Source: RevenueBase Database · checked Sep 21, 2026
3Indirect evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,0002,972 contacts →

Indirect evidence

“Control Risks is a global specialist risk consultancy that helps to create secure, compliant and resilient organisations.”

Source: RevenueBase Database · checked Sep 21, 2026
4Indirect evidenceWestcliff-on-sea, United KingdomHQ checked Sep 21, 20265,001-10,0001,842 contacts →

Indirect evidence

“Wilson James provides safe, secure, customer-led solutions to more than 300 clients across the UK and Europe.”

Source: RevenueBase Database · checked Sep 21, 2026
5Partial evidenceNorthampton, United KingdomHQ checked Sep 21, 202610001+1,508 contacts →

Partial evidence

“We are an intelligence-led security business.”

Source: RevenueBase Database · checked Sep 21, 2026
6Indirect evidenceLeatherhead, United KingdomHQ checked Sep 21, 20261,001-5,0001,437 contacts →

Indirect evidence

“With offices in the UK and Australia, Frazer-Nash is a leading systems, engineering and technology company.”

Source: RevenueBase Database · checked Sep 21, 2026
7Partial evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,000919 contacts →

Partial evidence

“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.”

Source: RevenueBase Database · checked Sep 21, 2026
8Partial evidenceLeeds, United KingdomHQ checked Sep 21, 20261,001-5,000884 contacts →

Partial evidence

“Professional Security is one of the UK’s leading providers of security services, specialising in the hospitality and events sectors.”

Source: RevenueBase Database · checked Sep 21, 2026
9Partial evidenceNorthampton, United KingdomHQ checked Sep 21, 20265,001-10,000852 contacts →

Partial evidence

“VSG are one of the UK's leading security solutions providers with a heritage in manned guarding.”

Source: RevenueBase Database · checked Sep 21, 2026
10Partial evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,000847 contacts →

Partial evidence

“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…”

Source: RevenueBase Database · checked Sep 21, 2026
11Partial evidenceUnited KingdomHQ checked Sep 21, 20261,001-5,000765 contacts →

Partial evidence

“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…”

Source: RevenueBase Database · checked Sep 21, 2026
12Strong evidenceLondon, United KingdomHQ checked Sep 21, 2026n/a705 contacts →

Strong evidence

“Get a free, powerful security assessment with personalised recommendations, the same analysis that costs from IT Consultancies.”

Source: RevenueBase Database · checked Sep 21, 2026
13Partial evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,000597 contacts →

Partial evidence

“Part of ICTS Europe Group, ICTS UK & Ireland is a professional services firm which has been specialised in security risk for the past 39+ years.”

Source: RevenueBase Database · checked Sep 21, 2026
14Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026501-1,000502 contacts →

Partial evidence

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

Source: RevenueBase Database · checked Sep 21, 2026
15Partial evidenceCirencester, United KingdomHQ checked Sep 21, 20261,001-5,000422 contacts →

Partial evidence

“Unlike traditional security providers, we're redefining what protection means in today's world.”

Source: RevenueBase Database · checked Sep 21, 2026
16Partial evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,000419 contacts →

Partial evidence

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

Source: RevenueBase Database · checked Sep 21, 2026
17Partial evidenceBlackburn, United KingdomHQ checked Sep 21, 2026n/a393 contacts →

Partial evidence

“At Global Security Ltd, we are proud to be one of the UK’s trusted suppliers of CCTV, intruder alarms, access control, and fire safety systems.”

Source: RevenueBase Database · checked Sep 21, 2026
18Indirect evidenceSwindon, United KingdomHQ checked Sep 21, 2026501-1,000392 contacts →

Indirect evidence

“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…”

Source: RevenueBase Database · checked Sep 21, 2026
19Partial evidenceManchester, United KingdomHQ checked Sep 21, 2026501-1,000389 contacts →

Partial evidence

“Mitie Fire & Security is part of Mitie, the UK’s leading facilities management and professional services company, delivering integrated fire and security solutions that protect…”

Source: RevenueBase Database · checked Sep 21, 2026
20Partial evidenceLondon, United KingdomHQ checked Sep 21, 20265,001-10,000358 contacts →

Partial evidence

“ASEL design, develop and deliver fully bespoke and integrated security solutions, seamlessly bringing together people, technology and processes to achieve results-driven outcomes.”

Source: RevenueBase Database · checked Sep 21, 2026
21Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-500351 contacts →

Partial evidence

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

Source: RevenueBase Database · checked Sep 21, 2026
22Partial evidenceAscot / Birmingham / Manchester / Glasgow, United KingdomHQ checked Sep 21, 2026201-500341 contacts →

Partial evidence

“We deliver complex fire protection and security solutions.”

Source: RevenueBase Database · checked Sep 21, 2026
23Indirect evidenceBradford, United KingdomHQ checked Sep 21, 2026501-1,000326 contacts →

Indirect evidence

“Kings Secure Technologies (KST) is a high-end, enterprise-level systems integrator.”

Source: RevenueBase Database · checked Sep 21, 2026
24Partial evidenceBraintree, United KingdomHQ checked Sep 21, 20261,001-5,000326 contacts →

Partial evidence

“Established in 1993, with commitment to our customers and staff alongside a strong ethos and standards driven approach, Regency Security is now the largest provider of door…”

Source: RevenueBase Database · checked Sep 21, 2026
25Partial evidenceChandlers Ford, United KingdomHQ checked Sep 21, 2026201-500324 contacts →

Partial evidence

“Established in 1992, Churches Fire & Security is a nationwide company dedicated to supplying customers with the best fire safety and security services.”

Source: RevenueBase Database · checked Sep 21, 2026

Showing 25 of 5,888 security consultancies based in the United Kingdom

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Security consultancies based in the United Kingdom at a glance

As of Sep 21, 2026
13.2%Verified-email coverage
27.1Average contacts per company
1-10Median size (employees)
26.5%Largest-city concentration · London
Sep 21, 2026Page data refreshed

Companies by employee count

1-10
3,267
11-50
1,611
51-200
707
201-500
173
501-1,000
44
1,001-5,000
33
5,001-10,000
8
10001+
6

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 5,888 companies.

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 security 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 “security 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 security 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 security 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, 21,044 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 21, 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 security 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 security consultancies are there based in the United Kingdom?

RevenueBase identified 5,888 security 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?

G4s, headquartered in London, tops this list with the largest team on record.

Which city has the most security consultancies?

London leads with 1559 headquartered companies, followed by Manchester (132) and Birmingham (101).

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 21,044 verified decision-maker contacts tracked across these 5,888 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 21, 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.