Company lists · Data refreshed September 2026
Top 25 Security monitoring service providers based in the United Kingdom
RevenueBase identified 1,145 security monitoring service providers headquartered in the United Kingdom as of September 2026 and tracks 103,554 professional contacts across them, including 5,523 with verified work emails and 8,590 with mobile numbers. London is the largest hub.
This list covers security monitoring service providers 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, how directly it supports the match, and when it was last checked. Data refreshed September 6, 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.
The 25 largest security monitoring service providers based in the United Kingdom
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 79,699 | ||||
“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: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 2 | 6,169 | ||||
“Making the world a safer place.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 3 | 1,508 | ||||
“We are an intelligence-led security business.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 4 | 847 | ||||
“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: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 5 | 422 | ||||
“Unlike traditional security providers, we're redefining what protection means in today's world.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 6 | 419 | ||||
“Ward is an award winning, privately owned business, providing bespoke risk and security solutions including protective security personnel, explosive search dogs, narcotic search…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 7 | 392 | ||||
“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: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 8 | 326 | ||||
“Kings Secure Technologies (KST) is a high-end, enterprise-level systems integrator.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 9 | 226 | ||||
“MAN Commercial is a leading security company and Training Academy based in Solihull, West Midlands.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 10 | 205 | ||||
“Pilgrims are a global security, risk management and service support company that identifies and manages risks for clients across all sectors, including oil & gas, telecoms…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 11 | 172 | ||||
Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 12 | 170 | ||||
“Looking after the things people care about, wherever they are’.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 13 | 166 | ||||
“Providing Exceptional Security Services to Corporate and Retail Customers - Brooknight Security, with over 30 years of experience, is the go-to choice for businesses seeking…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 14 | 166 | ||||
“Trigion Security Services is the UK provider of Security Guarding and Technical Solutions for Facilicom UK.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 15 | 137 | ||||
“The Keyholding Company are a tech-enabled mobile security services company, specialising in alarm response, mobile patrols, locks and unlocks, emergency and temporary guarding…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 16 | 116 | ||||
“TSP has a reputation for providing enterprise security solutions, as well as excellent system integration standards and exceptional aftercare support, since its founding in 1988.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 17 | 89 | ||||
“For a better service and competitive price try K4 Security Services At K4 we offer the following: 1.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 18 | 87 | ||||
“Croma Security Solutions Group (CSSG) began in 1970 as a family-run business in Shirley, Southampton, known as County Locksmiths.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 19 | 85 | ||||
“At Servoca Secure Solutions, we take great pride in delivering a multi-service security business; offering a range of complementary products and services to both the public and…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 20 | 81 | ||||
“Nationwide Security providing both physical and electrical security services throughout the UK.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 21 | 80 | ||||
“T3 Security is a leading National Security Company supplying clients across the UK with bespoke security services.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 22 | 70 | ||||
“With over 50 years’ experience in the security industry, Abel has grown to become one of the UK’s largest privately owned providers of electronic security systems.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 23 | 69 | ||||
“BauWatch secures your site and assets with rapidly deployed mobile video surveillance systems.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 24 | 69 | ||||
“Northern Security Ltd is a leading guarding, alarm response and electronic security business operating throughout the North of England and South West Scotland.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 25 | SSS Management ServicesStrong evidence | 68 | |||
“is a security and facilities management business with over 25 years’ experience in monitoring, checking and delivering contractor performance for clients.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
Showing 25 of 1,145 security monitoring service providers based in the United Kingdom
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 5,523 reachable decision-makers.
Free signup · no credit card
Security monitoring service providers based in the United Kingdom at a glance
As of Sep 6, 2026Companies by employee count
Verified emails by last verification
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 monitoring service providers, so some rows will be adjacent to the category rather than pure plays. The description and evidence 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 SmartSearch, 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 monitoring service providers”. Matching reads each company's description, not its industry code or its name.
- What we exclude
- Companies whose own description does not clearly place them among security monitoring service providers, 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 an evidence 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, 5,523 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 6, 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.
Security monitoring service providers by metro
Frequently asked
How many security monitoring service providers are there based in the United Kingdom?
RevenueBase identified 1,145 security monitoring service providers 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 monitoring service providers?
London leads with 192 headquartered companies, followed by Manchester (29) and Birmingham (26).
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 5,523 verified decision-maker contacts tracked across these 1,145 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 6, 2026.
Ready to reach these companies? Verified emails and direct dials for all 1,145 security monitoring service providers based in the United Kingdom. Start with a free account, no credit card.
Get the full listRelated lists
Security monitoring service providers by geography
- Security monitoring service providers based in the United States
- Security monitoring service providers based in Brazil
- Security monitoring service providers based in France
- Security monitoring service providers based in Canada
- Security monitoring service providers based in Germany
- Security monitoring service providers based in Australia
- Security monitoring service providers based in Italy
- Security monitoring service providers based in the Netherlands
- Security monitoring service providers based in South Africa
- Security monitoring service providers based in Mexico
- Security monitoring service providers based in Spain
- Security monitoring service providers based in Argentina
Browse the directory
Browse: Companies home · All United Kingdom lists · All Security monitoring service providers lists · New 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 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.
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- Security monitoring service providers based in the United States
- Security monitoring service providers based in Brazil
- Security monitoring service providers based in France
- Security monitoring service providers based in Canada
- Security monitoring service providers based in Germany
- Security monitoring service providers based in Australia