Company lists · Data refreshed September 2026

Top 22 Security guard and patrol services based in London, United Kingdom

RevenueBase identified 389 security guard and patrol services headquartered in London, United Kingdom as of September 2026 and tracks 87,344 professional contacts across them, including 1,081 with verified work emails. London is the largest hub.

This list covers security guard and patrol services headquartered in London, 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
389Companies
87,344Contacts tracked
1,081Verified emails
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The 22 largest security guard and patrol services based in London, United Kingdom

Ranked by team size
Top 22 of 389 security guard and patrol services based in London, 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 guard and patrol services: 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
2Partial evidenceLondon, United KingdomHQ checked Sep 21, 20265,001-10,0001,451 contacts →

Partial evidence

“TSS is the UK’s largest retail specialist security company, employing over 7500+ security personnel.”

Source: RevenueBase Database · checked Sep 21, 2026
3Partial 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
4Partial 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
5Partial 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
6Partial evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,000272 contacts →

Partial evidence

“VPS is Europe’s leading temporary security specialist, protecting vacant properties, remote sites, construction and infrastructure projects with tailored, risk-based security…”

Source: RevenueBase Database · checked Sep 21, 2026
7Indirect evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,000232 contacts →

Indirect evidence

“Established in 1994, Interr is a specialist agency providing intelligent guarding, reception, remote monitoring & response and front of house solutions within the retail, hotel…”

Source: RevenueBase Database · checked Sep 21, 2026
8Strong evidenceLondon, United KingdomHQ checked Sep 21, 202651-200137 contacts →

Strong evidence

“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: RevenueBase Database · checked Sep 21, 2026
9Strong evidenceLondon, United KingdomHQ checked Sep 21, 20261,001-5,000133 contacts →

Strong evidence

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

Source: RevenueBase Database · checked Sep 21, 2026
10Partial evidenceLondon, United KingdomHQ checked Sep 21, 202651-20085 contacts →

Partial evidence

“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: RevenueBase Database · checked Sep 21, 2026
11Partial evidenceLondon, United KingdomHQ checked Sep 21, 202651-20075 contacts →

Partial evidence

“We are Veteran Owned, Veteran Operated Security company based in London (HQ), with operation nationwide.”

Source: RevenueBase Database · checked Sep 21, 2026
12Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50071 contacts →

Partial evidence

“KK Security was established in 2014 with the goal of keeping people safe.”

Source: RevenueBase Database · checked Sep 21, 2026
13Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50064 contacts →

Partial evidence

“City Security Services (CSS) have more than 25 years’ experience within the corporate security, public sector, education and social housing markets delivering manned guarding…”

Source: RevenueBase Database · checked Sep 21, 2026
14Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50063 contacts →

Partial evidence

“Vigilance is a pioneering security company with a proud military heritage.”

Source: RevenueBase Database · checked Sep 21, 2026
15Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50058 contacts →

Partial evidence

“Black Diamond Security - Safeguarding Your World.”

Source: RevenueBase Database · checked Sep 21, 2026
16Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50045 contacts →

Partial evidence

“UK Protection is widely recognised as the premier supplier of security solutions to the Corporate, Jewellery and Luxury Retail industries across the UK.”

Source: RevenueBase Database · checked Sep 21, 2026
17Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026501-1,00043 contacts →

Partial evidence

“AK9 Security and FM Solutions offers comprehensive security solutions for businesses, governmental organizations, and residential areas.”

Source: RevenueBase Database · checked Sep 21, 2026
18Partial evidenceLondon, United KingdomHQ checked Sep 21, 202611-5037 contacts →

Partial evidence

“Founded in 2015, BML Group is one of the UK's leading Security & Facilities Management providers, delivering tailored solutions that enhance operational efficiency and safety.”

Source: RevenueBase Database · checked Sep 21, 2026
19Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50032 contacts →

Partial evidence

“Cerberus is one of the fastest-growing security service companies operating within the United Kingdom.”

Source: RevenueBase Database · checked Sep 21, 2026
20Strong evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50031 contacts →

Strong evidence

“Systematic Security deliver static manned guarding, mobile patrols, open and lock ups, keyholding and emergency response requirements as well as Vacant Property inspections to a…”

Source: RevenueBase Database · checked Sep 21, 2026
21Partial evidenceLondon, United KingdomHQ checked Sep 21, 2026201-50030 contacts →

Partial evidence

“Supplier of professional, high quality Security Guarding services-Corporate, retail and event security services-public and private function security-provision of Door Supervisors…”

Source: RevenueBase Database · checked Sep 21, 2026
22Partial evidenceLondon, United KingdomHQ checked Sep 21, 202651-20019 contacts →

Partial evidence

“The Portmarnock Group was built from years of experience, hard work and a genuine passion for doing security differently.”

Source: RevenueBase Database · checked Sep 21, 2026

Showing 22 of 389 security guard and patrol services based in London, United Kingdom

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Security guard and patrol services based in London, United Kingdom at a glance

As of Sep 21, 2026
1.2%Verified-email coverage
224.5Average contacts per company
11-50Median size (employees)
100.0%Largest-city concentration · London
Sep 21, 2026Page data refreshed

Companies by employee count

1-10
104
11-50
120
51-200
106
201-500
28
501-1,000
11
1,001-5,000
10
5,001-10,000
1
10001+
3

Email recency for this list is measured across the whole United Kingdom list rather than for London, so it is reported there. Company counts and contact totals on this page are exact for London, over 389 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 guard and patrol services, 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 London, United Kingdom whose own description of what they do matches “security guard and patrol services”. 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 guard and patrol services), 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 guard and patrol services, and records with no verified work email. Companies headquartered outside London 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, 1,081 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.

Security guard and patrol services by metro in the United Kingdom

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 guard and patrol services, 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 guard and patrol services are there based in London, United Kingdom?

RevenueBase identified 389 security guard and patrol services headquartered in London, 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 guard and patrol services?

London leads with 389 headquartered companies, followed by Birmingham (54) and Manchester (43).

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 1,081 verified decision-maker contacts tracked across these 389 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.