As the reliance on digital platforms grows, so does the complexity of cyber threats. Businesses are under constant pressure to secure their systems, data, and customer trust. Cyberattacks can disrupt operations, breach sensitive information, and cost companies millions in recovery. This article provides a curated list of the top 40 penetration testing companies in the UK for 2025, exploring their services, expertise, and why they stand out in this competitive field.
That’s where penetration testing becomes essential, as it acts as a simulated cyberattack on your systems to expose vulnerabilities before malicious actors do. It’s a vital step in your organization’s cybersecurity strategy that helps to identify and fix weak points to mitigate risks.
The UK, home to a booming tech ecosystem, boasts several top-tier companies specializing in penetration testing. Whether you’re a startup, SME, or enterprise, finding a reliable pen testing service provider can be revolutionary for your security posture.
What is Penetration Testing?
Penetration testing, often called pen testing, is a simulated cyberattack performed to evaluate the security of a system, application, or network. Unlike reactive measures, pen testing proactively identifies vulnerabilities, enabling organizations to fix weaknesses before they are exploited by actual cyber criminals.
Types of Penetration Testing
Penetration testing isn’t a one-size-fits-all solution. Depending on an organization’s needs, pen testing can take on several forms, each targeting specific aspects of IT infrastructure:
- Network Penetration Testing: Network pen testing focuses on uncovering vulnerabilities in internal or external networks, including firewalls, routers, and interconnected devices. It evaluates how well your network can withstand unauthorized access, ensuring attackers cannot exploit your network-based weaknesses.
- Web Application Penetration Testing: Web apps are prime targets for hackers seeking sensitive user data. This test analyzes aspects like authentication systems, app logic, and APIs to identify bugs and weaknesses.
- Wireless Penetration Testing: This test examines the security of an organization’s wireless networks, including Wi-Fi routers and endpoints. It ensures that wireless systems are protected against unauthorized access points or attacks.
- Cloud Penetration Testing: With businesses increasingly relying on cloud environments, this test assesses cloud infrastructure, storage, and configurations to detect misconfigurations, data exposure risks, and access control weaknesses.
- IoT Penetration Testing: IoT devices, from smart cameras to industrial sensors, often have security blind spots. This test identifies vulnerabilities in IoT ecosystems, including firmware, communication protocols, and device authentication.
- Mobile Application Penetration Testing: Mobile apps can be exploited through insecure data storage, weak authentication, or API flaws. This test evaluates an app’s security posture, ensuring data protection and resilience against cyber threats.
Key Benefits of Penetration Testing
- Risk Mitigation
Penetration testing reveals potential vulnerabilities before attackers can exploit them, enabling businesses to patch weaknesses promptly.
For example, a UK-based retail company might discover through pen testing that its point-of-sale (POS) systems are vulnerable to malware injections. By addressing this, they could prevent a potential financial loss from theft or fraud.
- Regulatory Compliance
Many industries require companies to adhere to strict cybersecurity standards like GDPR, PCI DSS, or ISO 27001. Pen testing ensures compliance by demonstrating that proactive security measures are in place.
- Data Protection
Protecting sensitive customer and business data is more crucial than ever. Regular pen tests reduce the risk of breaches, safeguarding critical information like financial records, personal data, or intellectual property.
- Customer Trust and Reputation
A secure business is a trustworthy business. Customers are more likely to engage with companies that prioritize their data’s safety, and demonstrating robust cybersecurity practices builds long-term trust.
Now that we’ve established the importance of pen testing, let’s explore the companies leading the charge in cybersecurity solutions across the UK.
Top 40 Penetration Testing Companies in the UK
1. QualySec – UK’s Top & Trusted Penetration Testing Company
When it comes to choosing the best and most trusted company, QualySec stands out as the go-to penetration testing service provider in the UK. With a strong reputation for excellence, process-based methodologies, and a client-centric approach, we’ve earned the trust of top enterprises and small businesses alike.
Why QualySec?
QualySec has built its reputation by offering a complete set of penetration testing services that cater to diverse needs. Their expertise includes but is not limited to web application testing, mobile application security assessments, network and infrastructure penetration testing, and even cloud security assessments.
Key Features of QualySec’s Services:
- Process-based Testing Method: We use data-driven processes along with manual and automated testing to ensure all vulnerabilities, including complex ones, are identified.
- Customized Reports: Rather than sending technical jargon-filled reports, QualySec delivers actionable insights designed to specific business needs. We assist you in addressing vulnerabilities with practical steps.
- Experienced Team: Our pen testing experts are certified and hold credentials like OSCP, CEH, and CISSP.
- Broad Sector Expertise: We’ve served clients in fintech, e-commerce, healthcare, IT, and various other industries.
Our unmatched track record and dedication to innovation make QualySec the first name you should consider when choosing penetration testing in the UK.
2. Nettitude
Nettitude is a global cybersecurity firm headquartered in the UK, specializing in advanced online penetration testing and threat intelligence. They are CREST-accredited and work across multiple industries.
Penetration Testing Services:
- Network Penetration Testing
- Web Application Testing
- Social Engineering
- Red Team Assessments
Benefits:
- CREST and CHECK certified
- Global presence with tailored solutions
- Strong focus on threat intelligence
3. SecureWorks
SecureWorks, based in London, offers comprehensive cybersecurity solutions with a strong emphasis on advanced automated penetration testing techniques. They serve both private and public sectors.
Penetration Testing Services:
- Network and Infrastructure Pen Testing
- Application Security Testing
- Wireless Network Testing
- Red Team and Blue Team Exercises
Benefits:
- Global threat intelligence capabilities
- 24/7 incident response support
- Strong reputation in enterprise security
4. F-Secure Consulting
F-Secure Consulting provides tailored cybersecurity and penetration testing consultancy. They focus on proactive threat detection and risk assessment.
Penetration Testing Services:
- Web Application Testing
- Mobile Application Testing
- Cloud Security Testing
- Advanced Red Team Operations
Benefits:
- Extensive experience in proactive threat detection
- Global cybersecurity network
- CREST-certified services
5. Cyberis
Cyberis specializes in cyber security penetration testing and cyber risk management. They provide detailed, actionable reports to help businesses improve their security posture.
Penetration Testing Services:
- Network and Infrastructure Testing
- Web and Mobile Application Testing
- Cloud Environment Assessments
- Social Engineering Tests
Benefits:
- Highly customer-focused approach
- Tailored security recommendations
- CREST-accredited
6. Pentest Limited
Pentest Limited, based in London, offers specialized penetration testing services with a focus on complex systems and emerging technologies.
Penetration Testing Services:
- Infrastructure Penetration Testing
- Web and Mobile Application Testing
- Cloud Security Testing
- IoT Device Pen Testing
Benefits:
- Strong focus on technical excellence
- Detailed, comprehensive reporting
- Long-standing reputation in the cybersecurity industry
7. CodeShield
CodeShield is a UK-based cybersecurity firm known for its innovative penetration testing methodologies tailored to modern tech environments.
Penetration Testing Services:
- Web Application Pen Testing
- Network Penetration Testing
- Cloud Security Assessments
- Social Engineering Simulations
Benefits:
- Focus on cutting-edge security challenges
- Cost-effective solutions
- Fast, reliable reporting
8. North IT
North IT offers a web app penetration testing service focused on identifying vulnerabilities in networks, applications, and infrastructure.
Penetration Testing Services:
- Infrastructure Penetration Testing
- Web and Mobile App Testing
- Network Security Assessments
- Cloud Pen Testing
Benefits:
- Quick turnaround times
- Affordable service packages
- Strong focus on SMEs
9. Bulletproof
Bulletproof is a CREST-certified cybersecurity company offering a wide range of penetration testing services to businesses of all sizes.
Penetration Testing Services:
- Web Application Testing
- Infrastructure Pen Testing
- Cloud Security Assessments
- Red Team Engagements
Benefits:
- CREST accreditation ensures quality
- Comprehensive security support services
- Focus on compliance with GDPR and ISO standards
10. Cognisys Group
Cognisys Group provides expert application penetration testing and cybersecurity consulting to help businesses strengthen their security posture.
Penetration Testing Services:
- External & Internal Infrastructure Testing
- Web & Mobile Application Testing
- Cloud Security Assessments
- Social Engineering Tests
Benefits:
- Focus on regulatory compliance
- Tailored services for different industries
- CREST-certified testers
11. NSFOCUS
NSFOCUS offers specialized web application penetration testing with a strong focus on continuous security testing and automation.
Penetration Testing Services:
- Automated Security Testing
- Web Application Pen Testing
- Infrastructure Security Assessments
- Cloud Security Testing
Benefits:
- Over two decades of experience
- Strong focus on automation and efficiency
- Certified cybersecurity professionals
12. NCC Group
NCC Group is a global leader in cybersecurity and risk mitigation, providing robust security penetration testing to secure critical infrastructures.
Penetration Testing Services:
- Network and Application Pen Testing
- Red Teaming and Social Engineering
- Cloud Security Assessments
- IoT Device Security Testing
Benefits:
- Global expertise with a local presence
- Comprehensive risk management solutions
- Industry-leading cybersecurity certifications
13. Context Information Security
Context Information Security specializes in advanced penetration testing and threat intelligence services, with a focus on high-risk sectors.
Penetration Testing Services:
- Application and Network Testing
- Red Team Operations
- Mobile Security Testing
- Incident Response Testing
Benefits:
- CREST and CHECK certified
- Strong government and enterprise client base
- Expertise in handling advanced persistent threats
14. MWR InfoSecurity
MWR InfoSecurity offers cutting-edge cybersecurity penetration testing and security consulting services, now part of F-Secure.
Penetration Testing Services:
- Web and Application Security Testing
- Network Infrastructure Assessments
- Advanced Threat Simulation
- Red and Purple Team Exercises
Benefits:
- Strong focus on research-driven methodologies
- Global presence with tailored local services
- Extensive experience in financial services security
15. Trustwave
Trustwave provides a range of cybersecurity services, including specialized penetration testing for businesses of all sizes.
Penetration Testing Services:
- Network and Application Testing
- Wireless Security Assessments
- Database and Cloud Security Testing
- Red Team Operations
Benefits:
- Managed Security Services integration
- Global Security Operations Centers (SOCs)
- Comprehensive compliance support
16. BAE Systems Applied Intelligence
BAE Systems Applied Intelligence offers high-end cybersecurity services with a strong focus on defence-grade penetration testing for small businesses.
Penetration Testing Services:
- Network and Infrastructure Testing
- Application and IoT Device Testing
- Red Teaming and Advanced Threat Emulation
- Cloud Security Testing
Benefits:
- Expertise in military-grade security
- Strong R&D focus
- Trusted by government agencies worldwide
17. Darktrace
Darktrace is a leader in AI-driven cybersecurity, offering innovative pentest online services alongside its flagship threat detection platform.
Penetration Testing Services:
- Network and Endpoint Security Testing
- AI-Driven Threat Simulation
- Cloud Security Assessments
- Advanced Red Team Exercises
Benefits:
- Cutting-edge AI technology integration
- Real-time threat detection capabilities
- Global security operations support
18. Portcullis (Part of Cisco)
Portcullis, now part of Cisco, offers advanced penetration testing services with deep expertise in secure network architecture.
Penetration Testing Services:
- Infrastructure Penetration Testing
- Web Application Security Testing
- Cloud Security Assessments
- Red and Blue Team Operations
Benefits:
- Backed by Cisco’s global security resources
- Strong focus on enterprise-grade solutions
- Expertise in network infrastructure security
19. SureCloud
SureCloud is one of the penetration testing companies uk integrated with its governance, risk, and compliance (GRC) platform.
Penetration Testing Services:
- Network and Application Pen Testing
- Cloud Security Assessments
- Red Teaming and Social Engineering
- Compliance Testing (PCI DSS, ISO 27001)
Benefits:
- Integrated risk management solutions
- Strong focus on compliance-driven security
- CREST-accredited services
20. Secarma
Secarma specializes in pen testing companies uk in offensive security, offering advanced penetration testing services with a focus on real-world attack simulations.
Penetration Testing Services:
- Infrastructure and Web Application Testing
- Red Team Engagements
- Cloud Security Testing
- Social Engineering Assessments
Benefits:
- Strong offensive security expertise
- Tailored threat simulation services
- CREST-certified professionals
21. Cygenta
Cygenta offers comprehensive cybersecurity consultancy with a strong emphasis on AWS penetration testing and security awareness.
Penetration Testing Services:
- Network and Application Penetration Testing
- Red Team Operations
- Cloud Security Assessments
- Physical Security Testing
Benefits:
- Holistic security approach
- Expertise in both technical and human factors
- Strong focus on security culture and awareness
22. CybSafe
CybSafe focuses on human-centric cybersecurity, offering penetration testing services designed to assess vulnerabilities in both technology and human behaviour.
Penetration Testing Services:
- Social Engineering Assessments
- Phishing Simulation Testing
- Web Application Penetration Testing
- Network Vulnerability Assessments
Benefits:
- Emphasis on human behaviour analytics
- Data-driven security solutions
- Strong focus on reducing human-related security risks
23. Trustwave
Trustwave is a leading cybersecurity company providing comprehensive cloud penetration testing services to help organizations identify and mitigate security risks.
Penetration Testing Services:
- Network and Application Pen Testing
- Database Security Assessments
- Cloud Penetration Testing
- Red Team Operations
Benefits:
- Global threat intelligence resources
- Strong focus on compliance and risk management
- 24/7 managed security services
24. Redscan
Redscan, a Kroll business, specializes in offensive security services, including penetration testing and threat detection.
Penetration Testing Services:
- External and Internal Network Pen Testing
- Web Application Security Testing
- Red Teaming and Adversary Simulation
- Wireless Security Assessments
Benefits:
- CREST-accredited
- Real-world attack simulations
- Expertise in threat hunting and incident response
25. Tenable
Tenable is renowned for its vulnerability management solutions, offering penetration testing services to complement its risk assessment tools.
Penetration Testing Services:
- Network Penetration Testing
- Application Security Testing
- Cloud Environment Security Assessments
- Continuous Vulnerability Management
Benefits:
- Industry-leading vulnerability management platform
- Integration with enterprise security tools
- Scalable solutions for large organizations
26. Blackfoot Cybersecurity
Blackfoot Cybersecurity provides expert penetration testing and risk assessment services to help organizations safeguard their critical assets.
Penetration Testing Services:
- Network Infrastructure Testing
- Web Application Security Testing
- Social Engineering Assessments
- Wireless Network Testing
Benefits:
- Tailored security solutions
- In-depth risk analysis and reporting
- Strong focus on compliance with industry standards
27. Risk Crew
Risk Crew provides comprehensive penetration testing in cyber security and security risk management services to businesses worldwide.
Penetration Testing Services:
- Network and Application Pen Testing
- Social Engineering Tests
- Wireless Security Assessments
- Physical Security Testing
Benefits:
- CREST-certified testers
- Tailored penetration testing strategies
- Focus on risk mitigation and security awareness
28. Tessian
Tessian uses machine learning to enhance cybersecurity practices, including penetration testing services tailored to modern threats.
Penetration Testing Services:
- Network Security Testing
- Application Pen Testing
- Cloud Security Assessments
- AI-Driven Threat Simulation
Benefits:
- Innovative AI-driven solutions
- Focus on email and human-layer security
- Strong reputation in data loss prevention
29. Portcullis Modern
Portcullis Modern offers advanced penetration testing services and security consultancy with a focus on high-risk industries.
Penetration Testing Services:
- Network and Infrastructure Pen Testing
- Application Security Assessments
- Red Team Engagements
- Wireless Security Testing
Benefits:
- Industry-leading expertise
- CREST and CHECK certified
- Tailored solutions for complex security needs
30. Contextual Security
Contextual Security, a part of Accenture Security, provides comprehensive penetration testing services with global reach.
Penetration Testing Services:
- Advanced Red Team Operations
- Web and Mobile Application Testing
- Cloud Infrastructure Assessments
- Threat Intelligence Services
Benefits:
- Global cybersecurity network
- Focus on critical national infrastructure
- Strong threat intelligence capabilities
31. Offensive Security
Offensive Security is a well-known cybersecurity training and penetration testing provider, famous for its industry-leading OSCP certification. The company specializes in ethical hacking and security assessments, equipping organizations with robust security solutions.
Penetration Testing Services:
- Network Penetration Testing
- Web Application Penetration Testing
- Wireless Security Testing
- Exploit Development
Benefits of Choosing Offensive Security:
- Expertise in ethical hacking and offensive security
- Hands-on approach with real-world attack simulations
- Globally recognized security training and certifications
32. Secarma
Secarma is a UK-based Penetration Testing as a Service platform consultancy offering expert penetration testing and security assessment services. They work with businesses of all sizes to strengthen cyber defences through tailored security solutions.
Penetration Testing Services:
- Infrastructure Penetration Testing
- Web Application Security Testing
- Mobile Application Security Testing
- Cloud Penetration Testing
- Red Team Assessments
Benefits of Choosing Secarma:
- Experienced security consultants with CREST and CHECK accreditations
- Custom security testing tailored to business needs
- In-depth reporting and remediation guidance
33. Aardwolf Security
Aardwolf Security is a UK-based cybersecurity firm specializing in penetration testing and vulnerability assessments. They focus on helping businesses identify and fix security flaws before attackers can exploit them.
Penetration Testing Services:
- Web Application Penetration Testing
- Network Security Testing
- Cloud Security Testing
- API Penetration Testing
Benefits of Choosing Aardwolf Security:
- Cost-effective penetration testing solutions
- Quick turnaround time with detailed reports
- Experienced security professionals ensuring high-quality assessments
34. Mitigate Cyber
Mitigate Cyber offers proactive cybersecurity services to protect businesses from cyber threats. Their network penetration testing services help organizations identify and fix security vulnerabilities effectively.
Penetration Testing Services:
- Web Application Security Testing
- Network Penetration Testing
- Cloud Security Testing
- Social Engineering Assessments
Benefits of Choosing Mitigate Cyber:
- Continuous security monitoring services available
- Advanced threat intelligence for better risk mitigation
- Comprehensive security training alongside penetration testing
35. Hacker House
Hacker House is a cybersecurity training and penetration testing firm specializing in offensive security strategies. They provide businesses with real-world attack simulations to enhance security posture.
Penetration Testing Services:
- Red Team Assessments
- Web Application Penetration Testing
- Network Security Assessments
- IoT Security Testing
Benefits of Choosing Hacker House:
- Real-world attack simulation from ethical hackers
- Training programs to upskill internal security teams
- Strong focus on offensive security techniques
36. Nettitude (LRQA)
Nettitude, a part of LRQA, is a leading cybersecurity consultancy providing a wide range of continuous penetration testing services. They help businesses mitigate cyber risks through advanced security testing.
Penetration Testing Services:
- Network Penetration Testing
- Web Application Security Testing
- Mobile Security Testing
- Red Team Operations
- IoT & Embedded System Testing
Benefits of Choosing Nettitude:
- Certified and accredited by CREST, CHECK, and PCI-DSS
- Industry-leading security assessments with a risk-based approach
- Custom security solutions for different industries
37. Trustnet
Trustnet is a cybersecurity and compliance solutions provider offering penetration testing and security assessments to protect businesses from cyber threats.
Penetration Testing Services:
- External & Internal Network Penetration Testing
- Web & Mobile Application Testing
- Cloud Security Assessments
- Compliance-Focused Security Testing (PCI-DSS, SOC2)
Benefits of Choosing Trustnet:
- Strong focus on compliance-driven security solutions
- Detailed security reporting with actionable insights
- Experienced cybersecurity professionals
38. Titania
Titania specializes in automated security auditing and penetration testing solutions. They focus on network security assessments and compliance validation.
Penetration Testing Services:
- Network Security Assessments
- Automated Vulnerability Assessments
- Compliance Audits (NIST, CIS, PCI-DSS)
Benefits of Choosing Titania:
- Automated security analysis for efficiency
- Compliance-driven security solutions
- Advanced reporting with actionable recommendations
39. Roke
Roke is a UK-based cybersecurity firm that provides advanced penetration testing services for enterprises, government, and defence organizations.
Penetration Testing Services:
- Red Teaming & Adversary Simulation
- Network & Infrastructure Security Testing
- Embedded System Security Assessments
- Threat Intelligence & Security Consulting
Benefits of Choosing Roke:
- Strong focus on government and defense-grade security
- Advanced research-driven security assessments
- Expertise in AI and machine learning security
40. Sapphire Cybersecurity
Sapphire Cybersecurity is a leading security consultancy that provides affordable penetration testing and managed security services to businesses.
Penetration Testing Services:
- Network & Infrastructure Penetration Testing
- Web & Mobile App Security Testing
- Cloud Security Assessments
- Red Team Exercises
Benefits of Choosing Sapphire Cybersecurity:
- 24/7 managed security services available
- Strong focus on threat intelligence and risk management
- Industry-recognized cybersecurity exp
Key Factors to Consider When Choosing a Pen Testing Company
With the increasing importance of cybersecurity, UK-based companies have built strong reputations for providing top-notch penetration testing services. But it’s important to understand the key qualities to look for in a pen testing company. Here are 5 factors to guide your decision-making:
1. Industry-Specific Experience
Not all penetration testing providers are equal. Some specialize in financial services, while others may focus on healthcare, retail, or SaaS. Choosing a company with proven experience in your specific industry ensures they understand the potential threats your organization faces and can tailor their testing methods accordingly.
2. Certifications and Accreditations
Certifications reflect a company’s expertise and adherence to industry standards. Look for providers accredited with:
- CREST (Council of Registered Ethical Security Testers): A leading certification for security companies in the UK.
- CHECK (CESG-Approved Penetration Testing): For companies qualified to serve UK government sectors.
- OSCP (Offensive Security Certified Professional): Demonstrating advanced individual pen-testing skills.
- ISO 27001 Certification: Proof of robust information security management standards.
These certifications indicate the company follows best practices and has reputable, qualified experts.
3. Comprehensive Reporting and Actionable Insights
A good penetration test should go beyond identifying vulnerabilities; it should offer detailed, actionable recommendations to address them. The reporting process should include:
- An executive summary for decision-makers.
- Detailed technical insights for IT teams.
- Prioritized remediation steps.
Ask potential providers for sample reports to evaluate the depth and quality of their findings.
4. Post-Assessment Support and Remediation Guidance
vulnerability and penetration testing doesn’t end with the report. The ideal company offers post-assessment support to help fix vulnerabilities and answer follow-up queries. Providers offering remediation guidance or tools for tracking and managing fixes add significant value.
5. Budget Considerations and Scalability
Different penetration testing companies offer various pricing models that range from one-time assessments to subscription-based services. Consider your budget and ensure the provider has
scalable options to grow with your organization, especially if your needs evolve.
FAQs
Q: How often should businesses conduct penetration tests?
A: At least once a year or after significant changes to infrastructure, applications, or security policies.
Q: What certifications should a good pen tester have?
A: Look for certifications like OSCP, CEH, CREST, or CISSP, which validate expertise in ethical hacking and security assessments.
Q: How do penetration tests differ from vulnerability assessments?
A: Penetration testing actively exploits vulnerabilities to assess real-world risks, while vulnerability assessments identify and list weaknesses without attempting exploitation.
Q: Are there regulations in the UK that mandate pentesting?
A: Yes, regulations like GDPR, PCI DSS, and NIS Directive require businesses handling sensitive data to conduct regular security assessments, including penetration testing.
Future of Penetration Testing Services
With rapidly evolving cybersecurity risks, penetration testing will remain a crucial component of
business security strategies in 2025 and beyond. Key trends to watch for include:
- Increased use of AI-driven testing tools for more intelligent threat insights.
- Focus on cloud security assessments as businesses increasingly migrate to cloud platforms.
- Greater demand for continuous pen testing to ensure year-round protection.
Organizations willing to invest in regular penetration testing and work closely with the right providers will succeed in the cyber resilience race.
Strengthen Your Security Today!
Choosing the right penetration testing company is critical to your cybersecurity defence strategy. Whether you’re a small business or an enterprise organization, the companies listed
above are equipped to help you identify and mitigate vulnerabilities effectively.
Don’t wait until a breach occurs to take action. Explore the top penetration testing companies in the UK for 2025 and make sure your systems are prepared to withstand the most sophisticated cyberattacks.
0 Comments