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Cybersecurity Companies in the UK: 1,803 Active Firms (2026)
Cybersecurity companies in the UK build software and services that protect systems, data and networks for organisations in a high-threat market.
Buying centres tend to sit in security operations, IT infrastructure, risk and compliance, and procurement teams rather than a single software owner. Suppliers sell to private-sector and public-sector organisations that handle regulated data, run cloud workloads, operate online services, or sit inside essential-service supply chains. Engagements range from point tools for vulnerability management or identity protection to retained managed security, incident response, secure cloud, and advisory work. The buying motion is often consultative: customers need evidence of technical capability, response coverage, accreditation and procurement fit before they commit, especially where outages, breach notification and third-party risk sit with senior management.
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1,803 cybersecurity companies are actively trading in the UK. That is a sizeable specialist supplier base rather than a small niche, but the shape remains uneven: many providers are advisory, managed-service or project-led businesses, while a narrower layer has revenue scale. Employment reporting points to a visible operating footprint, with 3,417 reported roles across the companies that disclose headcount. The mix is therefore not just pre-revenue software formation; it includes trading service teams, incident-response capacity and suppliers already embedded in business and public-sector procurement.
There is no single sector-wide licence for cyber security suppliers, but their work often sits beside client obligations under GDPR, the NIS regime and ICO oversight. Essential-service operators and relevant digital service providers, including online marketplaces, search services and cloud computing services, face activity-specific duties. Planned reforms under the Cyber Security and Resilience Bill would pull medium and large managed service providers closer to the regulated perimeter and require quicker reporting of harmful breaches. techUK and the UK Cyber Security Council give the sector some institutional coordination, while procurement remains shaped by client-side risk governance.
Demand appears sticky where cyber risk is tied to regulated data, cloud migration and supply-chain assurance, but the commercial shape is unlikely to be uniform. Managed services and advisory work tend to scale through people, coverage and client trust, while software-led models depend more on repeatable deployment and procurement access. The cohort has a long tail of specialist providers, so consolidation appears plausible as buyers simplify supplier estates and larger providers add incident response, identity and cloud security capability. Early-commercial firms may still find procurement slow where proof, insurance and accreditation matter.
1,803
Active firms
2026
179
Over £5M turnover
larger trading firms
132
New since 2022
recent incorporations
Key facts
About 9% of the trading cohort reports turnover above £5M (179 of 1,803 firms) — the rest sits below that revenue band.
7% of the cohort was incorporated since 2022 (132 firms), so a sizeable share is in its first few filing cycles.
The Network and Information Systems Regulations 2018 apply to operators of essential services and relevant digital service providers, including online marketplaces, online search engines and cloud computing services.
Cyber Security and Resilience Bill factsheets describe planned NIS reforms that would bring medium and large managed service providers into scope and require quicker reporting of harmful cyber breaches.
UK cyber security suppliers generated £13.2 billion in the most recent financial year, with c. £7.8 billion GVA and approximately 67,300 FTEs.
The UK exported £7.2 billion of cyber services in 2023 and was described as “the most targeted country in Europe for cyber attacks” in 2024.
Top UK Cybersecurity companies
RELIANCE CYBER SCIENCE LIMITED
Trajectory
5y · 2022–NowFinancial sub-scores
Computed from 5 filingsProvides managed cyber security services including network, cloud and identity security monitoring, managed detection and response, incident response, vulnerability management and security…
Serves B2B organisations across the UK and Ireland, particularly businesses with digital infrastructure, internal security teams, critical devices under management, and cyber risk, compliance or…
Financial Health
StableStable · -73% CAGR over 4y
Location
Trajectory
4y · 2023–NowFinancial sub-scores
Computed from 4 filingsDevelops cybersecurity software for security operations, providing a platform that combines SIEM, network detection and response (NDR), automation and case management to detect cyber threats, analyse…
Serves MSSPs and in-house SOC/security teams in organisations with data residency needs, especially education, public administration, financial services, critical infrastructure, healthcare, retail,…
Financial Health
WeakWeak · -26% CAGR over 3y
Location
PURECYBER LIMITED
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security services including managed 24/7 security operations centre (SOC) monitoring, threat detection, vulnerability scanning, penetration testing, incident response, and cyber…
Serves B2B and public/third-sector organisations needing cyber security support, with stated sectors including housing, manufacturing, education, accountancy, legal, financial services and retail.
Financial Health
HealthyHealthy · -44% CAGR over 5y
Location
ESENTIRE UK LIMITED
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsProvides managed detection and response cybersecurity services including 24/7 security operations centre monitoring, threat hunting, incident response and digital forensics. Develops an AI‑driven…
Serves mid-market businesses and public sector organisations needing managed cybersecurity, including finance, insurance, legal, healthcare, manufacturing, retail, construction, private equity, food…
Financial Health
HealthyHealthy · 0% CAGR over 1y
Location
ITHEALTH U.K. LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity services for healthcare organisations, particularly NHS bodies, including cyber assurance and compliance, identity and access management, threat monitoring and detection, and…
Serves NHS organisations and healthcare providers, including mental health trusts, commissioning support units, ambulance trusts and acute hospitals, with buyers in IT, cyber security and digital…
Financial Health
StableStable · -65% CAGR over 4y
Location
i3Secure Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security and information assurance consulting services, including penetration testing, vulnerability scanning, ISO 27001 and data protection consultancy, security architecture, Secure…
Serves UK public sector bodies and regulated organisations, including defence, NHS trusts, local councils, aviation and private-sector businesses needing security-cleared cyber and information…
Financial Health
StrongStrong · Growing, Hiring · 22% CAGR over 4y
Location
ARCANUM INFORMATION SECURITY LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security consultancy services including penetration testing, Cyber Essentials certification support, risk assessments, audits, digital forensics, compliance and governance advice, and…
Serves UK government and B2B organisations in defence, manufacturing, space, aviation, maritime, rail, critical national infrastructure, COMAH sites and other operational technology environments.
Financial Health
StableStable · Hiring · 28% CAGR over 2y
Location
NORMCYBER LIMITED
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides managed cyber security services including threat monitoring, managed detection and response, incident response, vulnerability management, email and cloud security, data protection,…
Serves businesses and organisations, with stated sector focus on financial services firms, industrial companies and housing associations; targets leadership, IT and security teams responsible for…
Financial Health
StrongStrong · Hiring · 27% CAGR over 4y
Location
Prism Infosec Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security services including penetration testing, red teaming, cloud security assessments, incident response, remediation, governance, risk and compliance consulting, and managed…
Serves organisations globally, including businesses of all sizes and public-sector bodies, with buyers such as security, IT, risk and governance leaders responsible for cyber resilience.
Financial Health
StrongStrong · Growing, Hiring · 23% CAGR over 4y
Location
BARRIER NETWORKS LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity consulting and managed security services, including security operations centre monitoring, penetration testing, vulnerability management, governance, risk and compliance…
Serves UK organisations from small businesses to large corporations and government agencies, including financial services, healthcare, education, logistics, retail, energy, legal, telecoms,…
Financial Health
WeakWeak · -60% CAGR over 4y
Location
SECON CYBER SECURITY LTD
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security consultancy and managed security services, including security architecture design, governance, risk and compliance advisory, zero trust strategy, incident response readiness,…
Serves UK businesses and other organisations, particularly IT and security leaders needing cyber security guidance, managed security services, risk management, compliance support, and incident…
Financial Health
StableStable · -20% CAGR over 2y
Location
Cybanetix Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides managed cybersecurity services including security operations centre (SOC) monitoring, managed detection and response, endpoint protection, firewall and email security, cloud security, and…
Serves business customers with IT infrastructure and cybersecurity/compliance needs, particularly organisations migrating from legacy security systems and seeking outsourced or managed security…
Financial Health
HealthyHealthy · Hiring · 44% CAGR over 4y
Location
Nine23 Limited
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsProvides high‑assurance managed IT services including cybersecurity advisory, risk assessment, private and hybrid cloud platforms, secure collaboration tools, and managed service integration for…
Serves UK public sector and B2B customers in HM Government, defence, national security, public safety, regulated sectors and their supply chains handling protectively marked data above OFFICIAL.
Financial Health
WeakWeak · Hiring · 26% CAGR over 1y
Location
CYBERCX UK LTD
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsProvides cyber security services including incident response, penetration testing, vulnerability assessments, managed security services, digital forensics, identity and access management, governance…
Serves UK enterprise and government organisations, including businesses of varying sizes in sectors such as wellness, information services and software development, and leaders responsible for cyber…
Financial Health
HealthyHealthy · 0% CAGR over 3y
Location
RELIANCE CYBER LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides managed cyber security services including monitoring and management of IT security infrastructure, managed detection and response, threat intelligence and vulnerability management. Also…
Serves businesses and organisations across the UK and Ireland, especially those with security teams, critical digital infrastructure, compliance needs, or exposure to cyber threats.
Financial Health
DistressedDistressed · -64% CAGR over 5y
Location
Cyber Security Specialists Limited
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security consultancy and managed security services including penetration testing, red teaming, vulnerability scanning, security awareness training, and virtual CISO/DPO support.…
Serves businesses, public-sector bodies and CNI organisations needing cyber security assurance, compliance support and managed security, including teams responsible for sensitive data, cloud,…
Financial Health
StrongStrong · Hiring · 73% CAGR over 2y
Location
DIGITALXRAID LTD
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security services including managed security operations centre (SOC), SIEM and XDR monitoring, penetration testing, incident response, vulnerability scanning, and compliance support…
Serves businesses and organisations needing outsourced cyber security and compliance support, especially IT and security leaders in regulated sectors with ISO 27001, SOC2, PCI DSS, Cyber Essentials,…
Financial Health
HealthyHealthy · Hiring · 24% CAGR over 4y
Location
ARCTIC WOLF NETWORKS UK LTD
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsProvides managed cybersecurity services including security monitoring, threat detection and response, incident response, risk assessment, and security awareness training. Operates a security…
Serves businesses and organisations with internal IT/security teams, including financial services, healthcare, legal, manufacturing, and sports and entertainment sectors, plus firms needing breach…
Financial Health
StrongStrong · Profitable, Growing, Hiring · 63% CAGR over 3y
Location
ZEPKO LIMITED
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsProvides managed cyber security services through a security operations centre, including continuous threat monitoring, incident response, penetration testing, breach assessment, and security…
Serves B2B organisations needing managed security operations, from local mid-market businesses to global enterprises, including firms seeking compliance, ecommerce protection, remote-working security…
Financial Health
StableStable · Hiring · 30% CAGR over 1y
Location
Jumpsec Limited
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cybersecurity consultancy and testing services, including penetration testing, red teaming, vulnerability scanning, cloud and web application security assessments, incident response, attack…
Targets UK organisations with security, risk or IT teams, including regulated businesses needing CREST/CHECK assurance, PCI DSS, DORA/TIBER-EU alignment, incident readiness and 24/7 security support.
Financial Health
DistressedDistressed · -12% CAGR over 2y
Location
NetSecurity.IO Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops cybersecurity software and provides services including endpoint threat detection and response, ransomware and data breach forensic investigations, incident response, managed detection and…
Serves enterprises, government agencies, MSSPs, and law enforcement/intelligence teams with endpoint security, incident response, digital forensics, SOC, and cyber risk needs.
Financial Health
StrongStrong · Growing, Hiring · 11% CAGR over 4y
Location
NOMIOS UK&I LIMITED
Trajectory
4y · 2019–NowFinancial sub-scores
Computed from 4 filingsProvides cybersecurity and network infrastructure services including managed detection and response, network management, security assessments, and design and integration of enterprise networking and…
Serves enterprises, service providers and public-sector organisations across industries including finance, healthcare, education, government, energy, retail, technology, telecommunications,…
Financial Health
HealthyHealthy · -39% CAGR over 6y
Location
CyberOne Limited
Trajectory
5y · 2022–NowFinancial sub-scores
Computed from 5 filingsProvides managed cyber security services including 24/7 threat monitoring, managed detection and response (MXDR), incident response, penetration testing, cloud and Microsoft security consulting, and…
Serves growth-focused B2B organisations using Microsoft security, especially in finance, banking and insurance, professional services, healthcare and life sciences, technology, retail, and…
Financial Health
WeakWeak
Location
Advanced Network Security Limited
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security services including security advisory and audits, network and infrastructure design, and managed security services. Helps organisations protect IT networks, data and systems…
Serves UK and global organisations, from consumer brands to frontline public services, across logistics, manufacturing, healthcare, education, finance, legal, retail, hospitality, and central and…
Financial Health
HealthyHealthy · -5% CAGR over 2y
Location
NEXOR LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security advisory services, research, and secure information exchange technologies. Develops products including software‑defined gateways, data diodes, and email and data guard systems…
Serves UK and allied public-sector defence, government and law enforcement agencies, plus critical national infrastructure enterprises and their supply chains handling classified or sensitive…
Financial Health
StableStable · -96% CAGR over 2y
Location
2T SECURITY LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security consulting and managed services including cyber risk reviews, Cyber Assessment Framework evaluations, security architecture design, cross‑domain solutions, virtual CISO…
Serves public sector and regulated organisations, including UK central government, defence and intelligence, telecoms, and critical national infrastructure operators with high-assurance security…
Financial Health
StrongStrong · Growing, Hiring · 39% CAGR over 4y
Location
HEIMDAL SECURITY UK LIMITED
Trajectory
4y · 2023–NowFinancial sub-scores
Computed from 4 filingsDevelops and provides a unified cybersecurity platform offering endpoint, network and email security, vulnerability and patch management, privileged access management, and threat detection and…
Sells to businesses and public sector organisations needing cybersecurity, including SMBs and enterprises in critical infrastructure, education, engineering, energy, government, healthcare,…
Financial Health
WeakWeak · 0% CAGR over 3y
Location
ALERT LOGIC UK LIMITED
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides managed cybersecurity services including continuous threat monitoring, detection and response across cloud, network, endpoint and application environments. Offers managed detection and…
Serves IT and security teams at businesses needing coverage across cloud, hybrid, on-premise, SaaS, web application and API environments, including organisations with compliance requirements such as…
Financial Health
DistressedDistressed · -59% CAGR over 4y
Location
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops and supplies digital security software and hardware, including software copy protection and licensing systems, multi-factor authentication tools, FIDO security keys, OTP tokens, smart cards,…
Serves B2B customers globally, from independent software companies to multinational corporations, including software vendors, IT/security teams and organisations managing user access control and…
Financial Health
StableStable · 0% CAGR over 4y
Location
Trajectory
4y · 2023–NowFinancial sub-scores
Computed from 4 filingsOperates a cybersecurity platform that runs bug bounty and vulnerability disclosure programs, connecting organisations with vetted ethical hackers to identify software vulnerabilities. Also provides…
Sells to businesses and public sector organisations running security testing programmes, especially teams in retail, gaming, finance, hospitality, SaaS, telecoms, transport, healthcare, media,…
Financial Health
StrongStrong · Hiring · 17% CAGR over 3y
Location
HACKERONE UK LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides a cybersecurity platform that connects organisations with a global community of security researchers to identify vulnerabilities. Offers bug bounty programmes, vulnerability disclosure…
Serves security and engineering teams at enterprises and public sector organisations, including financial services, healthcare, retail/e-commerce, automotive, crypto/blockchain, hospitality, US…
Financial Health
StrongStrong · Hiring · 26% CAGR over 2y
Location
Principle Networks Ltd
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity and network consultancy services including identity and access management, zero trust architecture, cloud security posture management, data protection, and network…
Serves enterprise organisations and their IT/security leaders needing cybersecurity, identity, zero trust, cloud security, data protection and network modernisation support.
Financial Health
StrongStrong · Growing, Hiring · 29% CAGR over 4y
Location
NOUVEAU SOLUTIONS LIMITED
Trajectory
3y · 2020–NowFinancial sub-scores
Computed from 3 filingsProvides cloud infrastructure and cybersecurity services, including hybrid cloud, infrastructure-as-a-service, Microsoft 365 solutions, managed detection and response, endpoint management, and…
Serves private-sector businesses, public sector bodies, telecom operators and service providers, with sector focus on financial services, hospitality, retail/e-commerce, transport/logistics, research…
Financial Health
WeakWeak · -2% CAGR over 2y
Location
Orpheus Cyber Limited
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber risk assessment and intelligence services, including external attack surface monitoring, third‑party risk management, vulnerability management, security testing, and regulatory…
Serves B2B and financial-sector buyers, including CISOs, cyber leaders, IT and infrastructure teams, DPOs, procurement and risk leaders, MSSPs, investment managers, and cyber insurers and brokers.
Financial Health
WeakWeak · -6% CAGR over 2y
Location
Cysiam Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security services including cyber threat intelligence, managed detection and response, security operations centre monitoring, threat hunting, incident response, and cyber security…
Serves public and private sector organisations globally, including the UK defence supply chain and operationally critical environments, where security and resilience risk is a priority.
Financial Health
StrongStrong · Growing, Hiring · 27% CAGR over 4y
Location
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides a crowdsourced cybersecurity platform that connects organisations with security researchers to identify software and infrastructure vulnerabilities. Offers bug bounty programmes, penetration…
Serves security buyers and teams at enterprises and public-sector organisations, especially in financial services, healthcare, retail, automotive, technology and security companies.
Financial Health
StrongStrong · Hiring · 39% CAGR over 2y
Location
Mondas Consulting Ltd
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity consulting and managed security services including SOC monitoring, SIEM log management, managed detection and response, vulnerability assessments, penetration testing, security…
Serves businesses and public sector organisations seeking cyber risk and compliance support, with stated focus on pharmaceutical, insurance, housing association, government, education and…
Financial Health
HealthyHealthy · Hiring · 29% CAGR over 4y
Location
SECQUEST INFORMATION SECURITY LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security consultancy and testing services, including penetration testing, network and application security assessments, internal infrastructure reviews, cloud security consulting, and…
Sells to organisations needing cyber security assurance, including banks, financial services firms, oil and gas companies, public sector bodies, government and MOD organisations, and other businesses…
Financial Health
HealthyHealthy · Hiring · 26% CAGR over 4y
Location
Salus Digital Security Limited
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity consultancy and managed security services including penetration testing, incident response, security auditing, secure architecture design, SOC maturity assessments, and data…
Serves businesses and public-sector organisations needing cybersecurity support, including regulated organisations, MOD suppliers, and teams responsible for data protection, infrastructure, cloud,…
Financial Health
StrongStrong · Growing, Hiring · 76% CAGR over 4y
Location
Equilibrium Security Services Ltd.
Trajectory
3y · 2022–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security consulting and testing services, including CREST penetration testing for web, network and mobile systems, red teaming and attack simulation, managed vulnerability scanning,…
Serves blue-chip brands, SMEs and public sector organisations across the UK, targeting CISOs, IT directors and business owners responsible for security, compliance and resilience within their…
Financial Health
DistressedDistressed · Hiring · 8% CAGR over 2y
Location
Threatscape Security Solutions Ltd
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security consulting, implementation and managed security services. Designs, deploys and supports endpoint, network, cloud and identity protection solutions, including Microsoft and…
Serves mid-sized and large organisations across sectors, especially IT and security teams responsible for endpoints, networks, cloud environments and Microsoft 365, with emphasis on clients needing…
Financial Health
HealthyHealthy · Hiring · 23% CAGR over 4y
Location
4SECURE LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDevelops cross-domain cybersecurity solutions that enable controlled data transfer between networks with different security classifications. Provides TrustedFilter software, data diode integrations,…
Targets defence stakeholders, central government bodies, critical national infrastructure operators, and commercial organisations managing classified or segregated IT/OT networks, especially where…
Financial Health
StrongStrong · Growing, Hiring · 35% CAGR over 2y
Location
Core to Cloud Ltd
Trajectory
3y · 2022–NowFinancial sub-scores
Computed from 3 filingsProvides cybersecurity services including continuous security assurance testing, dark web monitoring and threat intelligence, cyber crisis simulation, managed detection and response, and third‑party…
Serves UK organisations’ CISOs, IT teams and security leaders, including businesses needing cyber resilience support across internal operations, incident response and third-party supply chain risk.
Financial Health
WeakWeak · Hiring · 7% CAGR over 2y
Location
IP River Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity and network protection solutions including DDoS mitigation, API and bot protection, cloud and application security, penetration testing, and security assessments. Integrates…
Serves B2B and public sector buyers, especially banks, telecoms providers, military/defence organisations and government agencies seeking enterprise-grade cybersecurity, communications, data…
Financial Health
HealthyHealthy · Hiring · 6% CAGR over 4y
Location
LEFTBRAIN LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security consulting and managed security services for cloud‑based businesses, including ISO 27001 and Cyber Essentials certification support, virtual CISO and governance programmes,…
Serves B2B cloud-first and SaaS companies, especially fast-moving hybrid teams that need to pass enterprise due diligence, achieve ISO 27001 or Cyber Essentials certification, and support secure…
Financial Health
StrongStrong · Hiring · 20% CAGR over 4y
Location
Ayomide Colonel Ltd
Trajectory
4y · 2021–NowFinancial sub-scores
Computed from 4 filingsProvides cybersecurity services and software including ransomware protection, email encryption, data loss prevention, and endpoint security. Offers endpoint detection and response (EDR/XDR),…
Sells to B2B customers: company IT/security teams and managed service providers supporting end-client organisations, with messaging aimed at firms concerned about ransomware, spam, phishing and data…
Financial Health
StableStable · Hiring · 62% CAGR over 3y
Location
CYBERSEER LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides managed cybersecurity services including managed detection and response, SIEM, endpoint, network and cloud threat monitoring, and incident response. Operates security operations centre…
Sells to enterprise and mid-market businesses, primarily IT and security leaders needing outsourced cyber defence capacity across SIEM, endpoint, network and cloud environments.
Financial Health
StrongStrong · Growing, Hiring · 8% CAGR over 2y
Location
2-Sec Limited
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security consulting and assurance services including penetration testing, threat and vulnerability management, virtual CISO support, incident response planning, security awareness…
Sells to businesses needing cyber security, compliance and resilience support, including leadership teams, IT/security stakeholders and organisations pursuing standards such as PCI DSS, Cyber…
Financial Health
HealthyHealthy · -11% CAGR over 4y
Location
COMPUTER SECURITY TECHNOLOGY LTD.
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security services and information protection solutions, including security assessments, penetration testing, vulnerability management, policy and compliance support, and managed…
Serves business IT departments that lack in-house cybersecurity resources or specialist expertise, including organisations seeking independent security advice, managed security support, or Cyber…
Financial Health
WeakWeak · -6% CAGR over 2y
Location
Novacoast Limited
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsProvides cybersecurity consulting and managed security services, including penetration testing, identity and access management, security engineering, threat hunting, incident response, vulnerability…
Serves B2B and public-sector organisations with cybersecurity teams, especially CISOs and security programme leaders in healthcare, finance, staffing and federal sectors needing specialist support.
Financial Health
StrongStrong · Hiring · 14% CAGR over 3y
Location
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How UK Cybersecurity companies work and how to sell to them
What they do
Most cybersecurity suppliers earn revenue through a mix of subscription software, managed-service retainers, project fees and incident-response work. Software pricing typically follows users, endpoints, cloud workloads, log volume or protected assets, while managed security is more often sold on a monthly retainer with onboarding, service-level terms and optional out-of-hours cover. Advisory and testing work remains project-led, particularly for penetration testing, cloud reviews, governance work and audit preparation. Margins depend on the blend: repeatable software and standardised monitoring can scale through productised delivery, while incident response, assurance and bespoke architecture work rely more on senior technical staff and trust built over several engagements.
Who they sell to
Typical customers are mid-market and enterprise organisations, public-sector bodies, regulated digital services, financial services teams, healthcare operators, retailers and suppliers inside larger procurement chains. Smaller customers may buy a point tool or retained support through an IT manager, but larger contracts usually involve the chief information security officer, chief technology officer, head of infrastructure, risk, legal, procurement and finance. Direct sales is common for managed services and advisory work, with partner-led routes where cyber suppliers sit alongside cloud, telecoms or systems-integration relationships. Sales cycles tend to lengthen when buyers need accreditation checks, insurance approval, security questionnaires, references, service-level commitments and board-level risk sign-off.
What they buy
Most cybersecurity firms tend to spend on cloud hosting, lab environments, threat intelligence feeds, log storage, automation, ticketing, case management, CRM, billing, contract management and finance systems. Managed-service providers also need monitoring infrastructure, detection engineering tools, analyst workflow systems, knowledge bases, call-routing, reporting templates and customer portals. Service-led firms buy professional indemnity and cyber liability cover, specialist legal support, accreditation advice, training, recruitment, contractor networks and technical marketing. As headcount grows, HR, payroll, workforce planning and utilisation tools become more relevant, because delivery quality depends on analyst availability, certification coverage, response rota design and the ability to evidence work to clients.
Why and how to sell to them
Cybersecurity buyers tend to evaluate vendors when delivery strain becomes visible: too many alerts, slower onboarding, a new managed-service contract, a breach-response spike, a larger public-sector tender, or a client asking for better evidence of controls. Leadership change, fundraising, hiring across sales or security operations, and preparation for certification can also create budget. Outbound angles work better when they map to operational pain rather than generic fear: reducing analyst rework, improving audit trails, shortening customer reporting, protecting service margins, helping with supplier assurance, or making procurement evidence easier to produce. Claims need proof, because these buyers are used to testing vendor assertions.
How this list is built
Data sources
This list is built from UK Companies House filings, XBRL accounts data, and semantic analysis of each company's public website. Revenue and headcount figures come from the most recent filed accounts; where the company has not filed, values are estimated using a model trained on filed history and peer benchmarks and are labelled as estimates.
Classification
Rather than relying solely on SIC codes, Firmbase classifies each company semantically: the company's website is crawled, an AI model reads what the company actually sells, and the company is placed into the relevant industry and subsectors. SIC codes are used as one signal but not the only one. This means a company that registered under a generic SIC code but pivoted into (for example) fintech is correctly identified as fintech, not as its original SIC category.
Freshness
The underlying company data is refreshed from Companies House continuously; filings appear in the list within days of submission. The curated list ordering is regenerated when the underlying data moves meaningfully (company count changes by more than 5%, a new company enters the top-ranked segment, or the filed-revenue numbers for the top firms change). You can see the last-updated timestamp near the top of the page.
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