Company lists · Data refreshed September 2026
Top 25 Data security consulting firms based in the United Kingdom
RevenueBase identified 1,194 data security consulting firms headquartered in the United Kingdom as of September 2026 and tracks 9,824 professional contacts across them, including 2,984 with verified work emails and 549 with mobile numbers. London is the largest hub.
This list covers data security consulting firms headquartered in the 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 1, 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.
The 25 largest data security consulting firms based in the United Kingdom
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 739 contacts → | ||||
Partial evidence “SISA is a global forensics-driven cybersecurity solutions company, trusted by leading organizations for securing their businesses with robust preventive, detective, and corrective…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 2 | 387 contacts → | ||||
Partial evidence “At Resillion, we're more than just a global leader in quality engineering, testing, and cyber security – we're your dedicated partner from the start of your project to its…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 3 | 183 contacts → | ||||
Indirect evidence “For over 16 years, iBridge has helped many organizations in the legal, healthcare, manufacturing, utilities, financial, and education industries apply the latest technologies to…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 4 | 169 contacts → | ||||
Partial evidence “Ensuring your business is handling cyber security risks effectively has never been more important.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 5 | 165 contacts → | ||||
Indirect evidence “Sapphire delivers comprehensive cyber solutions tailored to your needs, spanning across consultancy, managed services, IT/OT and beyond.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 6 | 160 contacts → | ||||
Strong evidence “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…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 7 | 141 contacts → | ||||
Strong evidence “CyberSec Consulting, headquartered in the UAE and serving the iMETA market, is a distinguished professional Cyber Security and Consulting services company.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 8 | 123 contacts → | ||||
Indirect evidence “We are TRPGLOBAL, your strategic partner in helping you with the complexities of risk management.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 9 | 118 contacts → | ||||
Indirect evidence “Bulletproof is now part of WorkNest Secure.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 10 | 99 contacts → | ||||
Strong evidence “CyberSRC® is a CERT-in empanelled award winning organization, positioned to provide cyber security, data protection and assurance services with integrated security solutions…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 11 | 97 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 1, 2026Thanks. The Data Team will review it. | |||||
| 12 | 87 contacts → | ||||
Partial evidence “ITC Secure is an advisory-led cyber security services company.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 13 | 85 contacts → | ||||
Partial evidence “Solutions | Testing | Knowledge Helping You Protect Your Business From Cyber Attackers Your security and compliance partner, delivering trust worldwide Cognisys are your trusted…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 14 | 80 contacts → | ||||
Indirect evidence “At Reliance Cyber, we believe in truly partnering with our customers.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 15 | 80 contacts → | ||||
Strong evidence “Established in 2005, URM Consulting is a specialist provider of cyber and information security consultancy, training, and assurance services.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 16 | 73 contacts → | ||||
Partial evidence “Saepio increase awareness, reduce risk and improve security in a continually evolving threat landscape.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 17 | 61 contacts → | ||||
Indirect evidence “Many organisations are dealing with multiple frameworks, overlapping tools, disconnected ownership, and increasing pressure from regulators, customers, and boards.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 18 | 61 contacts → | ||||
Indirect evidence “We provide deep expertise with technical and business specialists to help clients secure and protect the UK.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 19 | 60 contacts → | ||||
Indirect evidence “In today’s advanced, interconnected world, protecting the infrastructure that allows society to function is crucial.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 20 | 56 contacts → | ||||
Partial evidence “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…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 21 | 52 contacts → | ||||
Partial evidence “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…” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 22 | 47 contacts → | ||||
Indirect evidence “In today’s complex threat environment, businesses, individuals, and organisations require trusted partners to provide the ultimate assurance that their assets are well protected.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 23 | 44 contacts → | ||||
Strong evidence “CornerStone is an award winning, independent, security and digital building consulting firm with headquarters in the UK.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 24 | 42 contacts → | ||||
Indirect evidence “Mitigo Group keeps professional services firms safe from cyberattack and operationally resilient.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
| 25 | 39 contacts → | ||||
Partial evidence “Lowers & Associates (L&A) is an independent and internationally recognized risk management consulting firm.” Source: RevenueBase Database · checked Sep 1, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: data security consulting firms. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names data security consulting firms.
- Partial evidence
- Its own public description names part of data security consulting firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name data security consulting firms. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 1,194 data security consulting firms based in the United Kingdom
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Data security consulting firms based in the United Kingdom at a glance
As of Sep 1, 2026Companies by employee count
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 data security consulting firms, 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 the United Kingdom whose own description of what they do matches “data security consulting firms”. 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 data security consulting firms), 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 data security consulting firms, and records with no verified work email. Companies headquartered outside United Kingdom 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, 2,984 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 1, 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.
Data security consulting firms by metro
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 data security consulting firms, 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 data security consulting firms are there based in the United Kingdom?
RevenueBase identified 1,194 data security consulting firms headquartered in the 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?
SISA, headquartered in Leicester, tops this list with the largest team on record.
Which city has the most data security consulting firms?
London leads with 449 headquartered companies, followed by Manchester (40) and Birmingham (24).
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 2,984 verified decision-maker contacts tracked across these 1,194 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 1, 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.
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