Company lists · Data refreshed September 2026

Top 11 Perimeter security contractors based in London, United Kingdom

RevenueBase identified 40 perimeter security contractors headquartered in London, United Kingdom as of September 2026 and tracks 656 professional contacts across them, including 329 with verified work emails and 44 with mobile numbers. London is the largest hub.

This list covers perimeter security contractors 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 13, 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 13, 2026 86% judged on-target in blind review
40Companies
656Contacts tracked
329Verified emails
44Mobile numbers
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The 11 largest perimeter security contractors based in London, United Kingdom

Ranked by team size
Top 11 of 40 perimeter security contractors based in London, United Kingdom, ranked by team size, largest first. Data refreshed Sep 13, 2026. RevenueBase Smart Search rates how each company's information relates to perimeter security contractors: 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 13, 202651-200159 contacts →

Partial evidence

“QCIC is an award-winning global engineering firm specialising in designing, building and running security systems.”

Source: RevenueBase Database · checked Sep 13, 2026
2Strong evidenceLondon, United KingdomHQ checked Sep 13, 20261,001-5,000136 contacts →

Strong evidence

“PRÆSIDIAD is a world market leader of force protection solutions,integrated perimeter security systems and industrial mesh production and fencing products.”

Source: RevenueBase Database · checked Sep 13, 2026
3Partial evidenceLondon, United KingdomHQ checked Sep 13, 202651-20051 contacts →

Partial evidence

“Established in Custom Intelligent Security is a technology driven ISO27001 & NSi Gold Accredited independent electronic security specialist with a proven track record of…”

Source: RevenueBase Database · checked Sep 13, 2026
4Indirect evidenceLondon, United KingdomHQ checked Sep 13, 202651-20049 contacts →

Indirect evidence

“Electranet’s mission is to be a preferred partner to the public and private sectors, bringing competitively priced, secure and innovative solutions to the market.”

Source: RevenueBase Database · checked Sep 13, 2026
5Partial evidenceLondon, United KingdomHQ checked Sep 13, 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 13, 2026
6Partial evidenceLondon, United KingdomHQ checked Sep 13, 202651-20039 contacts →

Partial evidence

“Gratte Brothers is an experienced provider of integrated security solutions, which are Built on Strong Values and ultimately deliver a measurable return on investment.”

Source: RevenueBase Database · checked Sep 13, 2026
7Partial evidenceLondon, United KingdomHQ checked Sep 13, 202651-20032 contacts →

Partial evidence

“Pafi Ltd, Was formed in 1995 to design, install and maintain integrated security solutions for the commercial market.”

Source: RevenueBase Database · checked Sep 13, 2026
8Partial evidenceLondon, United KingdomHQ checked Sep 13, 202651-20011 contacts →

Partial evidence

“The Security Group delivers state-of-the-art security solutions to protect businesses, assets, and people.”

Source: RevenueBase Database · checked Sep 13, 2026
9Partial evidenceLondon, United KingdomHQ checked Sep 13, 20261-1010 contacts →

Partial evidence

“London-based security company specialising in the design, installation, service and maintenance of single domestic, multi-occupancy residential and commercial security systems.”

Source: RevenueBase Database · checked Sep 13, 2026
10Indirect evidenceLondon, United KingdomHQ checked Sep 13, 202611-508 contacts →

Indirect evidence

“Our goal is so simple we can sum it up in one word - quality.”

Source: RevenueBase Database · checked Sep 13, 2026
11Partial evidenceLondon, United KingdomHQ checked Sep 13, 202611-504 contacts →

Partial evidence

“At Balthorne Security Solutions, we understand the risks people face and the importance of reliable security.”

Source: RevenueBase Database · checked Sep 13, 2026

Showing 11 of 40 perimeter security contractors based in London, United Kingdom

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Perimeter security contractors based in London, United Kingdom at a glance

As of Sep 13, 2026
50.2%Verified-email coverage
6.7%Mobile-number coverage
16.4Average contacts per company
11-50Median size (employees)
100.0%Largest-city concentration · London
Sep 13, 2026Page data refreshed

Companies by employee count

1-10
16
11-50
12
51-200
9
201-500
1
501-1,000
1
1,001-5,000
1

Freshness & accuracy

How recently the business emails were verified and the company information checked

Email last verified

Median 15.0d

Company record updated

Median 65.0d

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 perimeter security contractors, 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 “perimeter security contractors”. 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 perimeter security contractors), 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 perimeter security contractors, 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, 329 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 13, 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.

Perimeter security contractors by metro in the United Kingdom

  • Perimeter security contractors in London40

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 perimeter security contractors, 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 perimeter security contractors are there based in London, United Kingdom?

RevenueBase identified 40 perimeter security contractors 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?

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

Which city has the most perimeter security contractors?

London leads with 40 headquartered companies, followed by Manchester (10) and Leeds (8).

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 329 verified decision-maker contacts tracked across these 40 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 13, 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.