Company lists · Data refreshed September 2026

Top 25 Outsourced ciso services based in the United Kingdom

RevenueBase identified 782 company matches for outsourced ciso services associated with the United Kingdom as of September 2026 and tracks 7,745 professional contacts across them, including 3,118 with verified work emails. London is the largest hub.

This list covers company matches for outsourced ciso services 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 September 21, 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 Sep 21, 2026 How this list was built
782Companies
7,745Contacts tracked
3,118Verified emails
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The 25 largest outsourced ciso services based in the United Kingdom

Ranked by team size
Top 25 of 782 company matches for outsourced ciso services based in the United Kingdom, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 21, 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 matchReading, United KingdomHQ recorded Sep 21, 2026201-500303 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 · Sep 21, 2026 · View company records in RevenueBase
2Exact matchLeeds, United KingdomHQ recorded Sep 21, 2026201-500260 contacts →

Exact match

“We are a global boutique, specializing exclusively in the convergence of identity-driven security and networking.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
3Exact matchLondon, United KingdomHQ recorded Sep 21, 2026201-500190 contacts →

Exact match

“Intragen is a cyber security business focused on managed Identity solutions and services.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
4Exact matchNewcastle Upon Tyne, United KingdomHQ recorded Sep 21, 202651-200168 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 · Sep 21, 2026 · View company records in RevenueBase
5Exact matchThatcham, United KingdomHQ recorded Sep 21, 202651-200159 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 · Sep 21, 2026 · View company records in RevenueBase
6Exact matchMaidenhead, United KingdomHQ recorded Sep 21, 202651-200156 contacts →

Exact match

“Performanta is a global cybersecurity and data risk management company dedicated to protecting people where data matters most.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
7Exact matchFleet, United KingdomHQ recorded Sep 21, 202651-200125 contacts →

Exact match

“KHIPU Networks is an award winning international Cyber Security Company delivering a wide range of network, wireless and security solutions, technologies and services across…”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
8Exact matchLondon, United KingdomHQ recorded Sep 21, 202651-200123 contacts →

Exact match

“Bulletproof is now part of WorkNest Secure.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
9Exact matchLondon, United KingdomHQ recorded Sep 21, 2026201-50097 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
10Exact matchGuildford, United KingdomHQ recorded Sep 21, 202651-20093 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
11Exact matchStourport-on-severn, United KingdomHQ recorded Sep 21, 2026201-50086 contacts →

Exact match

“CyberGuard Technologies is the security division of Wavenet.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
12Exact matchBasingstoke, United KingdomHQ recorded Sep 21, 202611-5085 contacts →

Exact match

“Amethyst Risk Management is a leading cybersecurity consultancy supplying expert services and support to the UK Government, Defence, Operators of Essential Services, and the…”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
13Exact matchWaterloo, United KingdomHQ recorded Sep 21, 202651-20080 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
14Exact matchSouth & West Hampstead, United KingdomHQ recorded Sep 21, 202651-20079 contacts →

Exact match

“Virtual IT are a leading provider of cyber-secure cloud and managed IT services in the UK, entrusted by over 700 businesses and schools as their end-to-end technology partner.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
15Exact matchHigh Wycombe, United KingdomHQ recorded Sep 21, 202651-20074 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
16Exact matchOxford, United KingdomHQ recorded Sep 21, 202651-20073 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 · Sep 21, 2026 · View company records in RevenueBase
17Exact matchMilton Keynes, United KingdomHQ recorded Sep 21, 2026201-50073 contacts →

Exact match

“Bluecube - An Ekco Company Our mission is simple.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
18Exact matchDoncaster, United KingdomHQ recorded Sep 21, 202651-20062 contacts →

Exact match

“At DigitalXRAID, we’re more than just a managed security services provider – we’re your trusted partner in safeguarding your business from cyber threats.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
19Exact matchSouthampton, United KingdomHQ recorded Sep 21, 202651-20060 contacts →

Exact match

“Many organisations are dealing with multiple frameworks, overlapping tools, disconnected ownership, and increasing pressure from regulators, customers, and boards.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
20Exact matchAlderley Edge, United KingdomHQ recorded Sep 21, 202651-20057 contacts →

Exact match

“CyberLab is the UK-leading cyber security consultancy and managed services provider, trusted by over 1,200 enterprise businesses, government departments, and household names to…”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
21Exact matchLondon, United KingdomHQ recorded Sep 21, 202651-20052 contacts →

Exact match

“At Hexegic we are not just passionate about protecting data through our Cyber services we are passionate about helping companies release the potential of the data they hold…”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
22Exact matchCardiff, United KingdomHQ recorded Sep 21, 202611-5049 contacts →

Exact match

“PureCyber is an award-winning, expert Cyber Security Consultancy.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
23Exact matchLuton, United KingdomHQ recorded Sep 21, 202651-20045 contacts →

Exact match

“Established in 2004 (acquired by Gamma in 2023), Satisnet, a Gamma company is a pedigree-proven cyber security services and solutions specialist with a fully UK-based 24x7x365 SOC.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
24Exact matchCirencester, United KingdomHQ recorded Sep 21, 202611-5039 contacts →

Exact match

“We help organisations understand, optimise, and strengthen their cybersecurity.”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase
25Exact matchBrentford, United KingdomHQ recorded Sep 21, 202611-5039 contacts →

Exact match

“For over 20 years, we’ve helped businesses stay productive, secure and resilient through reliable IT support, modern cloud solutions and cyber security services designed for…”

Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase

Showing 25 of 782 outsourced ciso services based in the United Kingdom

See the full list, filter by size, metro and specialty, and access 3,118 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Outsourced ciso services based in the United Kingdom at a glance

As of Sep 21, 2026
40.3%Verified-email coverage
9.9Average contacts per company
1-10Median size (employees)
33.9%Largest-city concentration · London
Sep 21, 2026Page data refreshed

Companies by employee count

1-10
513
11-50
211
51-200
42
201-500
13
501-1,000
2

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 782 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 “outsourced ciso services” 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 3,118 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 September 21, 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 “outsourced ciso services”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many outsourced ciso services are there based in the United Kingdom?

RevenueBase identified 782 company matches for outsourced ciso services associated with the United Kingdom as of September 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?

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

Which city has the most outsourced ciso services?

London leads with 265 company records, followed by Manchester (30) and Birmingham (17).

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 3,118 professional contacts with verified work emails tracked across these 782 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 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 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.