Company lists · Data refreshed November 2026

Top 21 Managed security service providers based in the United Kingdom

RevenueBase identified 873 company matches for managed security service providers associated with the United Kingdom as of November 2026 and tracks 16,653 professional contacts across them, including 7,200 with verified work emails. London is the largest hub.

This list covers company matches for managed security service providers associated with the United Kingdom, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed November 5, 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.

How to read this list RevenueBase SmartSearch · Exact Recorded Nov 5, 2026 How this list was built
873Companies
16,653Contacts tracked
7,200Verified emails
Explore this list → Free signup · no credit card · 500 free credits

The 21 largest managed security service providers based in the United Kingdom

Ranked by team size
Top 21 of 873 company matches for managed security service providers based in the United Kingdom, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 5, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchAbingdon, United KingdomHQ recorded Nov 5, 20265,001-10,0005,283 contacts →

Exact match

“Sophos, a global cybersecurity leader, defends more than organizations worldwide with Sophos Fusion, the industry's first and most complete AI-native cybersecurity defense system…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
2Exact matchReading, United KingdomHQ recorded Nov 5, 2026201-500327 contacts →

Exact match

“Bridewell is the trusted cyber security partner for organisations operating within Critical National Infrastructure (CNI), as well as companies who want the highest standard of…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
3Exact matchNewcastle Upon Tyne, United KingdomHQ recorded Nov 5, 202651-200187 contacts →

Exact match

“Sapphire delivers comprehensive cyber solutions tailored to your needs, spanning across consultancy, managed services, IT/OT and beyond.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
4Exact matchDublin 8, United KingdomHQ recorded Nov 5, 202651-200184 contacts →

Exact match

“Qualcom provides ultra secure managed IT services using a security first ethos which maximises IT uptime and ensures that data is protected and accessible 24/7.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
5Exact matchMarlow, United KingdomHQ recorded Nov 5, 202651-200182 contacts →

Exact match

“24 x 7 Cloud Service Provider & Managed Security Service Provider delivering technology transformation.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
6Exact matchThatcham, United KingdomHQ recorded Nov 5, 202651-200161 contacts →

Exact match

“At Cyberfort we are passionate about the cyber security services we deliver for our customers which keeps their people, data, systems and technology infrastructure secure…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
7Exact matchLondon, United KingdomHQ recorded Nov 5, 202611-50127 contacts →

Exact match

“At Secon, we empower our clients to reach their full potential by taking the stress out of cyber security.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
8Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-200123 contacts →

Exact match

“Doherty Associates is a Managed Service Provider delivering IT support, cyber security and AI enablement ‘beyond the call’.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
9Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-200108 contacts →

Exact match

“CyberOne is a Microsoft Security Elite Partner and one of only 100 global Microsoft partners recognised with Microsoft-Verified Managed XDR solution status.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
10Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-200105 contacts →

Exact match

“Cybersecurity specialists providing technology and telecoms solutions that gives you the leadership, experience and resilience you need to build and secure the future of work.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
11Exact matchLeeds, United KingdomHQ recorded Nov 5, 202651-200101 contacts →

Exact match

“SEP2 is an award-winning UK-based cyber security specialist service provider, powered by a dedicated team of experts available 24/7/365.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
12Exact matchGuildford, United KingdomHQ recorded Nov 5, 202651-200100 contacts →

Exact match

“ramsac provide so much more than just IT support.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
13Exact matchStourport-on-severn, United KingdomHQ recorded Nov 5, 2026201-50090 contacts →

Exact match

“CyberGuard Technologies is the security division of Wavenet.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
14Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-20090 contacts →

Exact match

“Cybanetix is a leading provider of managed Cyber Security Service and hosted SIEM and breach detection services.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
15Exact matchHigh Wycombe, United KingdomHQ recorded Nov 5, 202651-20086 contacts →

Exact match

“Saepio increase awareness, reduce risk and improve security in a continually evolving threat landscape.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
16Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-20086 contacts →

Exact match

“ITC Secure is an advisory-led cyber security services company.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
17Exact matchWaterloo, United KingdomHQ recorded Nov 5, 202651-20084 contacts →

Exact match

“At Reliance Cyber, we believe in truly partnering with our customers.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
18Exact matchOld Trafford, United KingdomHQ recorded Nov 5, 20261,001-5,00080 contacts →

Exact match

“As a leading UK Managed Service Provider, we’re passionate about making technology work for you and integrating multiple products to create meaningful solutions.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
19Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-20077 contacts →

Exact match

“White Hat, part of the EPAM group, is an award-winning cyber intelligence and offensive security company that leverages an attacker’s perspective to shape innovative, proactive…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
20Exact matchOxford, United KingdomHQ recorded Nov 5, 202651-20076 contacts →

Exact match

“Dionach by Nomios has over 25 years of expertise in information security, supporting organisations in building resilience against ever‑evolving cyber threats.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
21Exact matchFareham, United KingdomHQ recorded Nov 5, 202651-20074 contacts →

Exact match

“Established in 2015, NormCyber is a multi-award-winning cyber security specialist, on a mission to provide organisations with complete visibility and total control over cyber risk.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase

Showing 21 of 873 managed security service providers based in the United Kingdom

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Managed security service providers based in the United Kingdom at a glance

As of Nov 5, 2026
43.2%Verified-email coverage
19.1Average contacts per company
1-10Median size (employees)
34.6%Largest-city concentration · London
Nov 5, 2026Page data refreshed

Companies by employee count

1-10
471
11-50
294
51-200
79
201-500
16
501-1,000
3
1,001-5,000
4
5,001-10,000
1

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 873 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

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
Company records associated with the United Kingdom whose business descriptions match “managed security service providers” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
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 displayed company carries at least one verified work email. RevenueBase tracks 7,200 professional contacts with verified work emails across the full matched dataset. 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 November 5, 2026. Lists refresh periodically as the graph is re-checked.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “managed security service providers”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many managed security service providers are there based in the United Kingdom?

RevenueBase identified 873 company matches for managed security service providers associated with the United Kingdom as of November 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Sophos tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most managed security service providers?

London leads with 302 company records, followed by Manchester (39) and Birmingham (18).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 7,200 professional contacts with verified work emails tracked across these 873 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on November 5, 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 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.