Company lists · Data refreshed September 2026

Top 25 Network security integrators based in London, United Kingdom

RevenueBase identified 95 network security integrators headquartered in London, United Kingdom as of September 2026 and tracks 835 professional contacts across them, including 323 with verified work emails. Across the United Kingdom, London is the largest hub for this category.

This list covers network security integrators 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 29, 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 29, 2026 86% judged on-target in blind review
95Companies
835Contacts tracked
323Verified emails
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The 25 largest network security integrators based in London, United Kingdom

Ranked by team size
Top 25 of 95 network security integrators based in London, United Kingdom, ranked by team size, largest first. Data refreshed Sep 29, 2026. RevenueBase Smart Search rates how each company's information relates to network security integrators: 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 29, 2026201-50097 contacts →

Partial evidence

“As an independent IT security specialist, Caretower provide comprehensive solutions to individual problems, thus allowing our recommendations to be unbiased.”

Source: RevenueBase Database · checked Sep 29, 2026
2Strong evidenceLondon, United KingdomHQ checked Sep 29, 2026201-50060 contacts →

Strong evidence

“Insoft Services specializes in elevating IT infrastructure resilience and security, focusing on the critical domains of IT networking, data center infrastructure, cybersecurity…”

Source: RevenueBase Database · checked Sep 29, 2026
3Partial evidenceLondon, United KingdomHQ checked Sep 29, 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 29, 2026
4Indirect evidenceLondon, United KingdomHQ checked Sep 29, 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 29, 2026
5Partial evidenceLondon, United KingdomHQ checked Sep 29, 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 29, 2026
6Partial evidenceLondon, United KingdomHQ checked Sep 29, 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 29, 2026
7Strong evidenceLondon, United KingdomHQ checked Sep 29, 202611-5024 contacts →

Strong evidence

“Principle Networks works with commercial and regulated organisations to reduce cyber risk and cost by simplifying security and network architecture.”

Source: RevenueBase Database · checked Sep 29, 2026
8Indirect evidenceLondon, United KingdomHQ checked Sep 29, 202611-5023 contacts →

Indirect evidence

“Toro was founded on creating the UK's first Red Team penetration test - and then attacking hundreds of clients by hacking their systems, influencing / social engineering staff and…”

Source: RevenueBase Database · checked Sep 29, 2026
9Partial evidenceLondon, United KingdomHQ checked Sep 29, 202611-5022 contacts →

Partial evidence

“Specialsing in cybersecurity, networks, voice and video, we're on a mission to transform workspaces and deliver exceptional outcomes for our clients.”

Source: RevenueBase Database · checked Sep 29, 2026
10Partial evidenceLondon, United KingdomHQ checked Sep 29, 202611-5020 contacts →

Partial evidence

“Formed in 2018, NGS (UK) Ltd are independent, Next Generation Security trusted advisors, providing all-encompassing solutions from the perimeter to the endpoint.”

Source: RevenueBase Database · checked Sep 29, 2026
11Partial evidenceLondon, United KingdomHQ checked Sep 29, 202611-5020 contacts →

Partial evidence

“Proxar IT Consulting provides IT services and security solutions for businesses of all sizes.”

Source: RevenueBase Database · checked Sep 29, 2026
12Indirect evidenceLondon, United KingdomHQ checked Sep 29, 202611-5017 contacts →

Indirect evidence

“We are a leading cybersecurity services organization with more than a decade of proven expertise in consulting, solution implementation and managed services.”

Source: RevenueBase Database · checked Sep 29, 2026
13Partial evidenceLondon, United KingdomHQ checked Sep 29, 202611-5017 contacts →

Partial evidence

“We are a London based specialist supplier of cyber defence solution and information security services.”

Source: RevenueBase Database · checked Sep 29, 2026
14Strong evidenceLondon, United KingdomHQ checked Sep 29, 20261-1014 contacts →

Strong evidence

“Alchem is a data and systems integrator providing high-end technical capabilities in the national security, defence, and critical infrastructure sectors.”

Source: RevenueBase Database · checked Sep 29, 2026
15Partial evidenceLondon, United KingdomHQ checked Sep 29, 202651-20014 contacts →

Partial evidence

“SYLVERSYS is a solutions integration firm with a specialty in providing secure computer and network products/solutions for businesses and organizations in the private and public…”

Source: RevenueBase Database · checked Sep 29, 2026
16Strong evidenceLondon, United KingdomHQ checked Sep 29, 20261-1012 contacts →

Strong evidence

“Our mission is to provide business customers with effective cloud network security solutions that enhance productivity, eliminate silos, reduce costs, and achieve digital…”

Source: RevenueBase Database · checked Sep 29, 2026
17Strong evidenceLondon, United KingdomHQ checked Sep 29, 202611-5010 contacts →

Strong evidence

“PC POWER INTERNATIONAL LTD is a computer & network security company based in the City, London, United Kingdom.”

Source: RevenueBase Database · checked Sep 29, 2026
18Partial evidenceLondon, United KingdomHQ checked Sep 29, 202611-5010 contacts →

Partial evidence

“Defenx is an IT company that has an extensive background in providing businesses with cloud based security solutions and support for their digital infrastructure.”

Source: RevenueBase Database · checked Sep 29, 2026
19Partial evidenceLondon, United KingdomHQ checked Sep 29, 202611-508 contacts →

Partial evidence

“iCyberDefence is a boutique cybersecurity services firm that offers a wide range of security consulting and security engineering services with the necessary products and tools.”

Source: RevenueBase Database · checked Sep 29, 2026
20Indirect evidenceLondon, United KingdomHQ checked Sep 29, 20261-107 contacts →

Indirect evidence

“Threat Protect is a vendor-agnostic cybersecurity, compliance and AI governance partner based in London, working with organisations across finance, legal, energy, pharma…”

Source: RevenueBase Database · checked Sep 29, 2026
21Indirect evidenceLondon, United KingdomHQ checked Sep 29, 202651-2006 contacts →

Indirect evidence

“Ansador Ltd has been privately owned since it was founded in 1982, providing system solutions to corporate and global clients across EMEA.”

Source: RevenueBase Database · checked Sep 29, 2026
22Indirect evidenceLondon, United KingdomHQ checked Sep 29, 20261-106 contacts →

Indirect evidence

“Since 2010, Bespoke Telecoms have been providing some of the of the finest business and residential properties in the Country with the fastest possible internet services…”

Source: RevenueBase Database · checked Sep 29, 2026
23Strong evidenceLondon, United KingdomHQ checked Sep 29, 20261-105 contacts →

Strong evidence

“London based security systems integrator presently engaged on some of the most existing London landmark buildings.”

Source: RevenueBase Database · checked Sep 29, 2026
24Indirect evidenceLondon, United KingdomHQ checked Sep 29, 202611-505 contacts →

Indirect evidence

“At Rexel Cyber we help businesses fight the constant threat of cyber attack and data breach.”

Source: RevenueBase Database · checked Sep 29, 2026
25Strong evidenceLondon, United KingdomHQ checked Sep 29, 20261-104 contacts →

Strong evidence

“is a leading provider of integrated network security and fire detection solutions.”

Source: RevenueBase Database · checked Sep 29, 2026

Showing 25 of 95 network security integrators based in London, United Kingdom

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Network security integrators based in London, United Kingdom at a glance

As of Sep 29, 2026
38.7%Verified-email coverage
8.8Average contacts per company
11-50Median size (employees)
Sep 29, 2026Page data refreshed

Companies by employee count

1-10
47
11-50
32
51-200
13
201-500
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 95 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 network security integrators, 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 “network security integrators”. 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 network security integrators), 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 network security integrators, 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, 323 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 29, 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 network security integrators, 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 network security integrators are there based in London, United Kingdom?

RevenueBase identified 95 network security integrators 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?

Caretower An Integrity360 Company, headquartered in London, tops this list with the largest team on record.

Which city in the United Kingdom has the most network security integrators?

London leads the United Kingdom with 95 headquartered companies, followed by Manchester (11) and Birmingham (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 323 verified decision-maker contacts tracked across these 95 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 29, 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.