Company lists · Data refreshed November 2026

Top 22 Secure software development firms based in the United Kingdom

RevenueBase identified 199 company matches for secure software development firms associated with the United Kingdom as of November 2026 and tracks 2,733 professional contacts across them, including 861 with verified work emails. London is the largest hub.

This list covers company matches for secure software development firms 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
199Companies
2,733Contacts tracked
861Verified emails
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The 22 largest secure software development firms based in the United Kingdom

Ranked by team size
Top 22 of 199 company matches for secure software development firms 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 matchLondon, United KingdomHQ recorded Nov 5, 2026501-1,000426 contacts →

Exact match

“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…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
2Exact matchKnutsford, United KingdomHQ recorded Nov 5, 202651-200288 contacts →

Exact match

“PortSwigger is a global leader in the creation of software tools for security testing of web applications.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
3Exact matchLondon, United KingdomHQ recorded Nov 5, 2026201-500104 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 · Nov 5, 2026 · View company records in RevenueBase
4Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-20072 contacts →

Exact match

“Gemba Advantage make high-impact software that is secure, scalable and sustainable.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
5Exact matchLondon, United KingdomHQ recorded Nov 5, 202651-20065 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
6Exact matchBasingstoke, United KingdomHQ recorded Nov 5, 202651-20063 contacts →

Exact match

“We’re here to provide world-leading vulnerability research and capabilities!”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
7Exact matchMacclesfield, United KingdomHQ recorded Nov 5, 202611-5057 contacts →

Exact match

“MDSec are a UK based consultancy with a passion for information security.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
8Exact matchLondon, United KingdomHQ recorded Nov 5, 202611-5053 contacts →

Exact match

“We deliver services in Cybersecurity, Application Security and DevOps and are trusted by some of the world’s leading brands to maximise the value of their security investments and…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
9Exact matchCheltenham, United KingdomHQ recorded Nov 5, 202651-20046 contacts →

Exact match

“CoreTech is a specialist cyber security company whose people are motivated by the desire to deliver exceptional capabilities coupled with a real sense of mission.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
10Exact matchMarlow, United KingdomHQ recorded Nov 5, 202611-5045 contacts →

Exact match

“DWS is a global enterprise software services company delivering development, testing, and software supply chain security solutions.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
11Exact matchRedruth, United KingdomHQ recorded Nov 5, 202651-20042 contacts →

Exact match

“Bluefruit Software’s UK-based embedded specialists work with innovative clients worldwide.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
12Exact matchManchester, United KingdomHQ recorded Nov 5, 202611-5042 contacts →

Exact match

“Secarma exists to keep the world safe.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
13Exact matchSolihull, United KingdomHQ recorded Nov 5, 202611-5035 contacts →

Exact match

“SPECIALISTS IN IT SECURITY AND COMPLIANCE Our goal is to help customers define, develop and implement information security and compliance services, no matter what stage of the…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
14Exact matchGloucestershire, United KingdomHQ recorded Nov 5, 202651-20031 contacts →

Exact match

“At Argo DevOps Solutions Ltd, our foundation is built upon a strong commitment to always do what is right for our people, customers, and our community.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
15Exact matchLeeds, United KingdomHQ recorded Nov 5, 202611-5023 contacts →

Exact match

“Halo I.S is not just another cybersecurity organization based in the UK; we're a testament to evolution and client-centric innovation.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
16Exact matchCrowborough, United KingdomHQ recorded Nov 5, 202611-5021 contacts →

Exact match

“Most technical partnerships start with requirements.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
17Exact matchManchester, United KingdomHQ recorded Nov 5, 202611-5020 contacts →

Exact match

“Cytix is the security decision layer for a world where software development never stops.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
18Exact matchCheltenham, United KingdomHQ recorded Nov 5, 202611-5020 contacts →

Exact match

“CloudSecure delivers secure software and cloud systems for security-critical environments.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
19Exact matchLondon, United KingdomHQ recorded Nov 5, 202611-5019 contacts →

Exact match

“Olive Jar Digital has extensive experience in building highly secure, resilient, highly available and scalable websites.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
20Exact matchMalvern, United KingdomHQ recorded Nov 5, 202611-5016 contacts →

Exact match

“Assure Technical are technical security experts.”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
21Exact matchBristol, United KingdomHQ recorded Nov 5, 202611-5014 contacts →

Exact match

“Cirrus Software Solutions provides the UK government with expertise in delivering high-quality secure software and systems engineering with a particular focus on transitioning to…”

Recorded in the RevenueBase company graph · Nov 5, 2026 · View company records in RevenueBase
22Exact matchBath, United KingdomHQ recorded Nov 5, 202611-5014 contacts →

Exact match

“At Mobius Binary we care about your reputation and the loss that could result from violating your digital boundaries.”

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

Showing 22 of 199 secure software development firms based in the United Kingdom

See the full list, filter by size, metro and specialty, and access 861 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Secure software development firms based in the United Kingdom at a glance

As of Nov 5, 2026
31.5%Verified-email coverage
13.7Average contacts per company
1-10Median size (employees)
40.7%Largest-city concentration · London
Nov 5, 2026Page data refreshed

Companies by employee count

1-10
128
11-50
52
51-200
10
201-500
2
501-1,000
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 199 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 “secure software development firms” 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 861 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.

Secure software development firms by metro

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 “secure software development firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many secure software development firms are there based in the United Kingdom?

RevenueBase identified 199 company matches for secure software development firms 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?

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

Which city has the most secure software development firms?

London leads with 81 company records, followed by Manchester (9) and Leeds (6).

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 861 professional contacts with verified work emails tracked across these 199 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.