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Cybersecurity Companies in London: 500+ Active Firms (2026)
Cybersecurity companies in London provide security software, consulting and managed services for organisations in a high-threat, regulation-tightening market.
Buying centres in London tend to sit across security operations, cloud and identity tooling, managed detection, incident response and governance work tied to audit or board risk. Buyers are usually CISOs, IT operations, risk and compliance teams, with procurement and legal involved where contracts touch regulated clients or personal data. The closer fit is B2B, mid-market to enterprise, and technology-led rather than consumer security. Engagements tend to combine recurring subscriptions or monitoring retainers with project work, so suppliers need both specialist delivery capacity and evidence that controls can survive client diligence.
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London has 511 actively trading cybersecurity companies, including 58 with turnover above £5M and 49 incorporated since 2022. Reported headcount totals 1,841 employees across firms with employment disclosure. The cohort is not just a set of advisory boutiques: revenue and staffing patterns point to a mix of product-led suppliers, managed-service operations and specialist consulting teams. London’s buyer base also matters, because operators of essential services, relevant digital service providers and other corporate customers tend to make cyber resilience a board and procurement issue rather than a narrow IT purchase.
Cybersecurity suppliers do not generally face a sector-wide licence. Their exposure is usually indirect, through client obligations under GDPR, the NIS regime and ICO expectations. Operators of essential services and relevant digital service providers can push security requirements into procurement, audit and incident-response clauses. Planned Cyber Security and Resilience Bill reforms would bring medium and large managed service providers closer to regulated status, with the Information Commission expected to oversee parts of that regime. NCSC guidance, techUK and the UK Cyber Security Council shape common language around controls, assurance and skills.
Demand appears to be shaped less by discretionary technology refreshes than by audit, insurance and breach-readiness pressure. London suppliers with managed-service and incident-response capacity tend to sit closer to recurring budgets, while advisory-only firms can be more exposed to procurement pauses. Scale-up scarcity may persist where buyers want referenceable delivery teams, security accreditation and round-the-clock cover before moving sensitive workloads. Planned NIS reforms also point towards a more formal buyer-supplier boundary, which could favour providers able to document controls, staffing and response processes without turning every engagement into bespoke consultancy.
511
Active firms
2026
58
Over £5M turnover
London cyber security firms
49
Incorporated since 2022
newer London entrants
Key facts
About 11% of the trading cohort reports turnover above £5M (58 of 511 firms) — the rest sits below that revenue band.
9% of the cohort was incorporated since 2022 (49 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.
The ICO is the competent authority for relevant digital service providers and can issue fines of up to £17 million in the most serious cases.
Planned Cyber Security and Resilience Bill reforms would bring medium and large managed service providers into scope and require quicker reporting of harmful cyber breaches.
DSIT’s 2025 sectoral analysis estimates 2,165 active UK firms providing cyber security products and services, compared with 2,091 in the 2024 analysis.
The UK exported £7.2 billion of cyber services in 2023 and was “the most targeted country in Europe for cyber attacks” in 2024.
Top London cybersecurity companies
Integrity360
Provides cyber security services including managed detection and response, threat monitoring, incident response, penetration testing, vulnerability management, and security operations. Also offers…
Serves organisations in the public sector and regulated industries including banking, fintech, healthcare, education, utilities, manufacturing, professional services and media across Europe.
Financial Health
Insufficient historyInsufficient history
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
COUNTERCRAFT LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops cybersecurity software that uses deception technology to create decoy environments within networks, generating threat intelligence, detecting attackers, and monitoring lateral movement and…
Serves enterprise CISOs and security teams, public infrastructure operators, governments and national security organisations, with focus on energy, financial services, healthcare, manufacturing,…
Financial Health
StableStable · Hiring · 26% CAGR over 4y
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
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
Vambrace
Provides cybersecurity consulting and managed security services, including compliance support for standards such as ISO 27001, Cyber Essentials and PCI DSS, penetration testing, vulnerability…
Sells to businesses seeking cybersecurity, compliance and risk management support, including teams responsible for security operations, compliance and supplier risk. Serves organisations needing…
Location
BLOCKPHISH LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security and AI security advisory services, including risk assessments, incident response, managed security services, penetration testing, physical security consulting, and support for…
Serves UK organisations, especially critical national infrastructure operators, enterprises and public-sector bodies with CIO/CISO-led security needs.
Financial Health
HealthyHealthy · Hiring · 53% CAGR over 4y
Location
FIELD EFFECT SECURITY LTD
Trajectory
4y · 2021–NowFinancial sub-scores
Computed from 4 filingsProvides cybersecurity software and services including a managed detection and response (MDR) platform that monitors endpoints, networks and cloud systems. Also offers incident response, security…
Serves managed service providers, SMEs, and internal IT/security teams at businesses of varying sizes, including organisations needing cybersecurity support for themselves or their clients.
Financial Health
StrongStrong · Hiring · 24% CAGR over 4y
Location
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDevelops cybersecurity software that protects critical IT infrastructure from ransomware attacks. Provides tools for ransomware containment, server intrusion protection, and virtual server security,…
Serves B2B and public-sector organisations with critical IT infrastructure, targeting CISOs and cybersecurity teams in education, finance, government, healthcare, legal and manufacturing sectors.
Financial Health
StrongStrong · Hiring · 17% CAGR over 2y
Location
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides a cybersecurity platform that assesses and quantifies cyber risk, maps potential attack routes, and prioritises mitigation. Also offers advisory, assessment, and incident response services…
Serves enterprise and mid-market organizations in healthcare, financial services, critical infrastructure, technology and retail, targeting CISOs, security operations leaders, risk officers, red…
Financial Health
HealthyHealthy · Hiring · 50% CAGR over 4y
Location
DIGITAL SAMURAI LTD
Trajectory
5y · 2022–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity services including risk assessments, penetration testing, vulnerability assessments, incident response, and managed detection and response. Also offers compliance support such…
Serves organisations requiring cybersecurity support, especially in healthcare, finance, retail and logistics, plus governments and institutions needing cybercrime defence and regulatory compliance.
Financial Health
WeakWeak · Hiring · 122% CAGR over 3y
Location
Sophos
Develops and provides cybersecurity software and managed security services, including endpoint protection, firewalls, email and cloud security, threat detection and response, and managed detection…
Serves businesses and public-sector organisations needing cybersecurity, including education, financial services, government, healthcare, manufacturing and retail, plus channel partners, managed…
Location
Opswat
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsDevelops cybersecurity software and hardware for protecting IT and operational technology environments. Products include malware scanning, file sanitization, network detection and response, email and…
Sells primarily to B2B and public sector organisations operating critical infrastructure and industrial environments, including IT and OT security teams, enterprises, and partners needing…
Financial Health
StrongStrong · Hiring · 28% CAGR over 3y
Location
Provides corporate intelligence and cyber security consulting services, including cyber incident response, managed security, digital forensics, offensive security testing, due diligence, disputes and…
Serves businesses and organisations worldwide across sectors, particularly corporate leadership, security teams, deal teams, investors, and legal or compliance teams facing cyber, transaction,…
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
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cybersecurity consulting and services including incident response, threat hunting, managed detection and response (MDR), cyber readiness assessments, red and purple team testing, threat…
Serves global enterprises and CISOs, including organisations in crypto, retail, financial services, healthcare, law, logistics and transportation, industrial systems, telecoms and technology.
Financial Health
WeakWeak · -13% CAGR over 2y
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
CYPFER LIMITED
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsProvides cybersecurity incident response and ransomware recovery services. Conducts digital forensics, breach and cloud investigations, dark web monitoring, and cyber risk assessments, and offers…
Serves businesses, critical infrastructure operators and organisations with legal/eDiscovery needs worldwide, targeting security, IT, risk and legal teams responding to cyber incidents or managing…
Financial Health
StableStable · Hiring · 122% CAGR over 1y
Location
Foresight Cyber
Trajectory
2y · 2024–NowProvides cybersecurity advisory and consulting services, including security strategy and governance, board‑level risk advisory, penetration testing, compliance audits, cloud security reviews, red…
Serves B2B organisations in regulated sectors and global enterprises, targeting boards, CTOs, CISOs, IT directors and security leaders in fintech, healthcare, manufacturing, semiconductor, legal and…
Financial Health
Insufficient historyInsufficient history
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
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
QUOD ORBIS LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops a cybersecurity platform for continuous controls monitoring that aggregates data from IT systems to track security controls, risk and compliance status. Also provides consultancy including…
Serves mid-market and enterprise organisations, particularly security, risk and compliance leaders in regulated sectors with cyber governance, operational resilience and compliance requirements.
Financial Health
WeakWeak · Hiring · 13% CAGR over 4y
Location
THREATAWARE LTD
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsDevelops a cybersecurity management platform that integrates with existing IT and security tools to discover devices, monitor asset inventories, validate controls such as EDR and MFA, and automate…
Serves B2B security and IT teams at larger organisations with complex device estates, including legal, finance, energy and retail companies, as well as CISOs responsible for cyber asset protection.
Financial Health
StableStable · Hiring · 53% CAGR over 1y
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
THREATSPIKE LABS LIMITED
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsProvides subscription-based managed IT and cybersecurity services, including 24/7 helpdesk support, cloud and infrastructure management, incident detection and response, vulnerability scanning, and…
Serves B2B organisations globally, from fast-moving scale-ups to enterprises operating across multiple countries, particularly teams needing ongoing IT, cybersecurity, compliance and security testing…
Financial Health
StrongStrong · Growing, Hiring · 40% 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
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
FIRST RESPONSE (EUROPE) LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides cybersecurity, digital forensics and incident response services. Offers Microsoft 365 security assessments, Active Directory audits, managed security operations centre monitoring, and…
Serves organisations needing cyber resilience and incident support, including banks, law firms, energy and manufacturing companies, and public sector bodies, with emphasis on Microsoft 365 users.
Financial Health
StrongStrong · Hiring · 4% CAGR over 4y
Location
Provides cyber security and digital risk services including penetration testing, incident response, digital forensics, threat intelligence, and social engineering assessments. Also offers compliance…
Sells to businesses, UK government and public sector bodies, international government organisations, NGOs, online platforms, and defence-sector suppliers needing cyber security, compliance, digital…
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
Abacus Group
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsProvides managed IT services, cloud hosting, and cybersecurity solutions for financial services firms, including compliance support, disaster recovery, managed detection and response, vulnerability…
Serves B2B financial services firms globally, especially investment firms needing outsourced or co-managed IT, cloud, cybersecurity and compliance support for distributed workforces.
Financial Health
StrongStrong · Hiring · 116% CAGR over 1y
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
KNIGHT TRADING UK LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides managed cybersecurity services including penetration testing, software code signing, hardware security module (HSM) management, endpoint and cloud security, security consulting, compliance…
Serves enterprises and businesses across diverse industries that need managed cybersecurity, cloud security and compliance support, including organisations with complex digital infrastructure and…
Financial Health
HealthyHealthy · Hiring · 24% CAGR over 4y
Location
Charles Square Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsProvides managed IT support, cybersecurity services, cloud infrastructure and IT procurement for financial sector organisations. Also offers governance and ISO27001 compliance support, network…
Serves financial services businesses globally, including hedge funds, investment banks, proprietary trading firms, asset managers, fund of funds and private equity houses, from start-ups to large…
Financial Health
StableStable · -62% CAGR over 4y
Location
Infratech Systems Limited
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides managed IT services, cloud solutions, cybersecurity, and IT consultancy. Delivers infrastructure design, technology engineering, backup and disaster recovery, and AI consulting and…
Serves UK startups, SMBs and enterprises, with clients in financial services, retail, insurance, manufacturing and defence, plus public sector bodies including NHS, transport organisations,…
Financial Health
StrongStrong
Location
KOMPINGO LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cybersecurity distribution and support services for IT security vendors and channel partners. Offers managed security services, MDR, penetration testing, vCISO, compliance consulting, and…
Serves B2B cybersecurity vendors, IT security start-ups and channel partners, as well as organisations seeking managed security, compliance, vCISO, penetration testing and professional support.
Financial Health
WeakWeak · -90% 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
Acubed IT Solutions Limited
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDevelops secure cross-domain software systems enabling information sharing across air‑gapped and classified networks for government, defence, and critical infrastructure. Builds applications using a…
Serves government, defence and critical national infrastructure organisations, including UK public sector security teams, defence primes and classified-environment programme teams needing…
Financial Health
WeakWeak · Hiring · 22% 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
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDevelops browser-based cybersecurity software that monitors user browser sessions to detect and respond to threats such as phishing, malicious extensions, credential theft, and account takeover,…
Sells to B2B security leaders, CISOs, security operations and IT teams at organisations whose employees use browsers, SaaS and cloud accounts, including companies exposed to phishing, account…
Financial Health
StableStable · Hiring · 143% CAGR over 2y
Location
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsDevelops cybersecurity analytics software for maritime fleets and other operational assets. Provides monitoring of shipboard IT, IoT and OT systems, asset inventory, threat detection, cyber risk…
Serves maritime fleet operators and critical national infrastructure asset operators managing remote IT, IoT and OT systems, with buyers responsible for cybersecurity, cyber risk and compliance.
Financial Health
HealthyHealthy · Hiring · 44% CAGR over 1y
Location
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops cyber risk management software that analyses organisations’ internet‑facing assets and supply chains to identify vulnerabilities and exposures. Provides data and analytics tools used by…
Serves B2B organisations of any size and industry, including cyber insurance brokers, underwriters, financial services firms, public entities, and teams managing internal, supplier, client, or…
Financial Health
HealthyHealthy · Hiring · 28% CAGR over 4y
Location
Infosec K2K Ltd
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsProvides cybersecurity consulting and services focused on identity and access management (IAM), including IAM assessments, implementation, application onboarding, managed security services,…
Serves global organisations, particularly IT and security teams in regulated sectors requiring identity and access management, cybersecurity assurance, operational technology security, managed…
Financial Health
StrongStrong · Growing, Hiring · 26% CAGR over 3y
Location
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops cybersecurity software and services for managing cyber risk. Provides attack surface management, vulnerability scanning, digital risk protection, penetration testing, and threat intelligence…
Sells to B2B security, IT and risk teams at organisations needing cyber risk management, attack surface visibility, application security testing, threat intelligence and PCI compliance support.
Financial Health
StableStable · Hiring · 6% CAGR over 4y
Location
TORO RISK SOLUTIONS - GLOBAL LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber, physical and converged security services including risk assessments, security audits, penetration testing, incident response, managed detection and response, investigations, due…
Serves businesses, government and public sector organisations seeking cyber, physical and investigative security support, typically engaging risk, security, IT and resilience leaders responsible for…
Financial Health
StrongStrong · Hiring · 38% CAGR over 2y
Location
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber threat intelligence software and services, including a SaaS platform that collects and analyses data on threat actors, vulnerabilities, breaches and underground marketplaces to support…
Serves B2B security teams and cyber risk leaders at organisations with exposure to advanced cyber threats, including teams managing threat intelligence, threat hunting, attack surface exposure and…
Financial Health
HealthyHealthy · -8% CAGR over 2y
Location
Icyberdefence Limited
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsProvides cyber security consulting and advisory services, including security architecture design, network segmentation, security risk assessments, and remediation. Supports organisations with…
Serves large enterprises and public sector organisations in regulated sectors, including rail, pharmaceuticals, life sciences, telecoms, financial services, utilities and transport, across the UK,…
Financial Health
StrongStrong · Growing, Hiring · 109% CAGR over 4y
Location
FORTIS CYBER SECURITY LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides cyber security consultancy and information security services, including penetration testing, Cyber Essentials and IASME certification support, ISO management system certification…
Serves organisations of all sizes, particularly financial services firms, corporate enterprises, and government and defence bodies with information security and risk management requirements.
Financial Health
StableStable · Hiring · 26% CAGR over 2y
Location
Prevalent AI Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops cybersecurity software that integrates security and asset data into a unified knowledge graph to provide exposure management. The platform identifies attack surfaces, prioritises…
Sells to B2B cybersecurity and IT security teams in organisations managing complex digital assets, identities, cloud environments and attack surfaces, particularly buyers responsible for risk…
Financial Health
WeakWeak · 0% CAGR over 4y
Location
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsProvides cybersecurity and risk management services including identity and access security, penetration testing, security monitoring, data discovery, and advisory services. Supports organisations in…
Serves businesses and large organisations needing organisational and digital resilience, including blue-chip customers, global enterprises, channel resellers and sectors such as financial services…
Financial Health
HealthyHealthy · Profitable, Hiring · 9% CAGR over 1y
Location
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How London cybersecurity companies work and how to sell to them
What they do
London cybersecurity suppliers usually earn revenue through a mix of subscription software, managed monitoring retainers, incident-response call-off arrangements and advisory projects. Product-led firms sell licences for tooling used by security operations, cloud teams or identity owners, often with implementation and support wrapped around the licence. Service-led firms bill retainers for monitoring and response, then add project fees for assessments, remediation, testing or audit preparation. Margins depend on whether delivery is repeatable or consultancy-heavy; buyers tend to reward evidence of process, clear escalation routes and staff who can work inside sensitive client environments.
Who they sell to
Most sell to regulated or risk-conscious organisations rather than consumers: financial services teams, SaaS operators, public-sector buyers and larger corporates with board-level exposure to breach, audit and insurance pressure. Decision-makers typically include the CISO, CTO, Head of IT, Head of Risk, Data Protection Officer and procurement, with legal involved where the supplier handles logs, credentials or personal data. Smaller deals may start as a paid assessment or narrow deployment, while larger engagements move through security questionnaires, RFPs, proof of value and contractual liability review. Direct sales dominates at scale, although channel and consulting partners can influence shortlists where the buyer has outsourced IT.
What they buy
Cybersecurity firms tend to buy tooling that shortens delivery time and reduces manual evidence work. Common spend areas include CRM, sales operations, proposal management, contract review, professional-services automation, ticketing, case management, cloud infrastructure, log storage, identity administration and secure development workflows. Managed-service providers also need workforce scheduling, customer reporting, alert triage and knowledge-management systems, because handover quality matters when incidents move between analysts. Consulting-heavy firms often spend on accreditation support, legal advice, finance systems, recruitment and specialist training. Marketing purchases are usually easier to justify when they support technical credibility: analyst relations, content for risk buyers, events aimed at CISOs and demand generation tied to specific compliance triggers.
Why and how to sell to them
Buying intent often appears when a provider wins a larger client, moves from project work into managed service delivery, hires senior revenue or operations staff, or starts preparing for tougher supplier assurance. Other triggers include security accreditation, cyber-insurance renewal, a breach response surge, a new public-sector route to market, or planned NIS reforms affecting managed-service providers. Sellers should usually lead with operational risk rather than generic efficiency: fewer handoffs during incidents, cleaner audit trails, faster client onboarding, better utilisation of scarce specialists, or lower exposure to contract penalties. Evidence matters; case studies by buyer type, implementation effort and control mapping usually land better than broad claims about cyber maturity.
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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