In today’s digital landscape, cybersecurity is not optional—it’s essential. Businesses of all sizes rely on web application penetration testing services to identify vulnerabilities before hackers do. These services simulate real-world attacks, uncover security gaps, and help organizations strengthen their defences.
Below are the top 12 best penetration testing providers in the United Kingdom, each offering advanced web application security, compliance testing, and threat-mitigation expertise.
Best Web Application Penetration Testing Services
1. Bulletproof
🔗 Visit 
Bulletproof is one of the UK’s most trusted cybersecurity firms, known for its CREST-certified web application penetration testing services. They simulate real-world attacks on web apps, APIs, and authentication systems to detect flaws in logic, access control, and data handling.
Their testers identify everything from injection vulnerabilities and broken authentication to advanced business logic flaws. Bulletproof also provides a post-engagement dashboard for ongoing monitoring and a full year of free vulnerability scanning — perfect for businesses wanting continuous assurance.
Highlights:
CREST & ISO 27001 certified testers
OWASP Top 10 methodology
Includes vulnerability scanning and retesting
Strong post-testing reporting and support
2. CyberLab
🔗 Visit CyberLab
CyberLab is a powerful UK security partner offering comprehensive web application penetration testing services for enterprises and SMEs. Their team of CREST, CHECK, and Cyber Scheme-certified testers help identify weaknesses across web apps, APIs, and networks.
Their in-house platform, CyberLab Control, gives clients real-time visibility into testing results, remediation progress, and ongoing threat intelligence. They’re trusted by financial institutions, retail brands, and the public sector for their deep expertise in cloud and hybrid environments.
Highlights:
Continuous security testing and monitoring
Cyber Essentials Plus certified provider
Combines manual and automated web app testing
Offers ongoing retesting and vulnerability management
3. Wavenet
Wavenet is a UK managed IT and security provider that delivers web application penetration testing under its CyberGuard division. They’re known for integrating testing into broader managed services, including SOC, MDR, and compliance solutions.
Businesses looking for a unified IT and security partner will find Wavenet ideal. Their approach ensures that vulnerabilities discovered during pen tests translate directly into actionable defense improvements.
Highlights:
Managed security + testing hybrid provider
24/7 SOC integration
CyberGuard division focused on offensive testing
Good fit for mid-to-large enterprises
4. Arcanum
🔗 Arcanum – Penetration Testing
Arcanum Cyber Security is an NCSC-Assured and CREST-accredited provider offering advanced web application penetration testing services. Their consultants have military and government backgrounds, giving them experience in high-sensitivity testing environments.
They deliver tailored engagements covering web, API, and infrastructure penetration testing with a strong emphasis on executive-level reporting. Their testers simulate complex attack chains including privilege escalation and lateral movement across app environments.
Highlights:
NCSC & CREST accredited
Specialists in government and critical infrastructure testing
Risk-based testing approach with technical and business reporting
Experienced security professionals with defence backgrounds
5. Evalian
🔗 Evalian – Penetration Testing
Evalian offers a balanced mix of consultancy and web application penetration testing services designed for organizations seeking both compliance and technical assurance. Their penetration testing process follows NCSC CHECK standards and is performed by experienced testers.
Evalian provides detailed scoping advice before engagements, ensuring you only test what’s necessary while maximizing ROI. Their post-test recommendations include remediation guidance aligned with ISO 27001 and Cyber Essentials frameworks.
Highlights:
CREST-certified team
Strong compliance focus (GDPR, ISO, NIS)
Executive-friendly vulnerability reports
Excellent client education and consultancy
6. North IT
North IT is a UK-based cybersecurity firm specializing in web application penetration testing services. Their small but skilled team performs deep manual assessments focused on business logic, access control, and configuration weaknesses.
They prioritize clarity, offering detailed reports that guide development teams through remediation. North IT’s flexibility makes them ideal for SMEs or startups needing expert testing without enterprise-level complexity.
Highlights:
Manual testing focus (no over-reliance on scanners)
Ideal for SMBs and SaaS providers
Fast project turnaround
Personalised service with dedicated tester contact
7. Astra Security (GetAstra)
Astra Security provides modern penetration testing-as-a-service (PTaaS) that blends manual and automated testing for web apps, APIs, and cloud systems. While global in reach, Astra supports many UK clients and aligns with UK compliance needs like Cyber Essentials and ISO 27001.
Their testing dashboard offers continuous monitoring, developer collaboration, and automated re-testing once fixes are applied — perfect for DevOps teams running CI/CD pipelines.
Highlights:
PTaaS (Pen Testing as a Service) model
Integrates with CI/CD and DevOps
Continuous retesting and vulnerability tracking
Real-time dashboard for developers
8. Pentest People
Pentest People are pioneers of the SecurePortal, a platform that helps clients track vulnerabilities, schedule retests, and collaborate with testers. Their web application penetration testing services cover OWASP Top 10 issues and business logic flaws, and they provide both one-off and continuous testing options.
They’re particularly popular with small and medium-sized enterprises looking for affordable yet thorough security testing.
Highlights:
SecurePortal for test tracking
Continuous pen testing option
OWASP Top 10 coverage
Affordable pricing tiers
9. Delta Cyber Security
Delta Cyber Security focuses on providing ethical hacking and web application penetration testing services to UK SMEs and local authorities. Their testers analyze every layer of your web app — from authentication to session management — ensuring vulnerabilities are fixed before threat actors find them.
Highlights:
UK-based ethical hackers
Specializes in SME security testing
Cost-effective testing packages
Personalised service for small businesses
10. DigitalXRAID
DigitalXRAID is ISO 27001 and Cyber Essentials certified, delivering advanced web application penetration testing services across the UK. They simulate sophisticated cyberattacks to uncover vulnerabilities and provide clear remediation roadmaps.
Their testing is ideal for regulated industries that require compliance reports for ISO, PCI-DSS, or GDPR audits.
Highlights:
Cyber Essentials & ISO certified
PCI-DSS testing specialists
Custom reporting for compliance
Strong government and enterprise client base
11.Claranet Cyber Security
🔗 Visit Claranet Cyber Security
Claranet is an experienced UK-based provider offering web application penetration testing services through their CREST-approved ethical hackers. They test for vulnerabilities like XSS, CSRF, broken authentication, and privilege escalation.
Claranet’s testers focus on both public and internal web apps, APIs, and SaaS platforms — ensuring secure development and deployment throughout the lifecycle.
Highlights:
CREST & ISO accredited testers
Application, cloud, and network testing
Deep experience with large enterprises
Offers managed detection and response (MDR)
12. NCC Group
NCC Group is one of the largest cybersecurity consultancies globally, with a strong UK presence. They provide world-class web application penetration testing services for enterprises across sectors such as finance, healthcare, and technology.
Their testing teams simulate complex attack vectors including injection flaws, logic bypasses, and privilege escalations. They’re a trusted name in the UK’s CREST and CHECK testing communities.
Highlights:
Enterprise-grade web app testing
Global experience with UK expertise
Ideal for regulated sectors (finance, telecom, gov)
Offers red teaming, SOC, and secure code review