Best CREST Penetration Testing Companies (2026)
CREST accreditation is the gold standard for penetration testing quality assurance. CREST-accredited companies undergo rigorous assessment of their testing methodologies, staff qualifications, and data handling practices. Choosing a CREST-accredited provider gives you confidence that your penetration test will be conducted to the highest professional standards.
Below are the top CREST-accredited penetration testing providers, ranked by our comprehensive scoring methodology that evaluates accreditation, team expertise, review quality, and service breadth.
Related: CHECK pen testing companies · CBEST-accredited companies · Pen testing companies in the UK
SECFORCE
Our top recommendation on this page.
Canary Wharf-based adversary simulation and CBEST-aligned penetration testing consultancy, delivering CREST-accredited offensive security to UK financial services and other organisations with the most demanding requirements.
- CBEST-approved provider staffed by certified CCRTM and CCRTS consultants.
- Has delivered over 15 CBEST engagements for UK high street banks, major financial institutions, and other regulated entities.
- Works with a network of trusted, CBEST-approved threat intelligence partners, and can also work alongside any threat intelligence provider selected by the client or regulator.
- Independently audited against both ISO 27001 and SOC 2 for information security, data handling, and operational integrity.
NCC Group
Global cybersecurity consultancy with CREST, CHECK, and CBEST accreditation, renowned for deep technical research and comprehensive penetration testing services.
Dionach
Global enterprise cybersecurity consultancy founded in 1999 in Oxford, holding rare CREST STAR-FS accreditation and delivering penetration testing, red and purple teaming, and PCI QSA services across five international offices.
NetSPI
Penetration testing firm trusted by nine of the top ten US banks, with the Resolve platform for continuous attack surface management.
Pen Test Partners
The UK's largest independent security testing firm, renowned for IoT/OT research, CBEST red teaming, and CHECK/CREST-accredited penetration testing across all sectors.
PwC Cyber Security
Global Big Four professional services firm delivering CREST, CHECK, and CBEST-accredited penetration testing and red teaming services from London, serving the UK's largest enterprises and regulated organisations.
MDSec
Elite UK offensive security consultancy specialising in CBEST/STAR/TIBER red teaming, advanced adversary simulation, and CREST-accredited penetration testing for FTSE 100 clients.
Trustwave
Global managed security provider with the elite SpiderLabs penetration testing team and deep PCI DSS compliance expertise.
Secarma
Manchester-based independent cybersecurity consultancy with over 20 years of experience delivering CREST and CHECK-accredited penetration testing, red teaming, and compliance certification services.
Cyberis
CREST and CHECK-accredited UK penetration testing consultancy with CBEST approval, specialising in infrastructure, application, and simulated attack assessments across the public and private sectors.
Aristi
CHECK and CREST-accredited Birmingham-based cyber security consultancy with over 15 years of experience delivering penetration testing, red teaming, and OT security assessments for government and private sector clients.
Bridewell
Fast-growing CREST and CHECK-accredited UK cybersecurity consultancy with deep expertise in critical national infrastructure sectors.
Best CREST Penetration Testing Companies (2026), FAQs
What is CREST accreditation for penetration testing?+
CREST (Council of Registered Ethical Security Testers) is an international accreditation body that certifies the competence and professionalism of cybersecurity service providers. CREST-accredited pen testing companies have demonstrated rigorous standards for methodology, staff qualifications, data handling, and reporting quality.
Why should I choose a CREST-accredited pen testing company?+
CREST accreditation provides assurance that the company follows industry-recognised standards, employs qualified testers, uses proven methodologies, and handles your data securely. Many compliance frameworks and regulators specifically recommend or require CREST-accredited testing.
Is CREST accreditation recognised globally?+
Yes. CREST is recognised internationally and has member companies across the UK, Europe, Asia-Pacific, and the Americas. CREST is particularly well-established in the UK, Australia, and Singapore, and is increasingly recognised in other regions.
What is the difference between CREST and CHECK?+
CREST accredits commercial penetration testing services. CHECK is a UK government scheme operated by the NCSC specifically for testing government systems. Many UK pen testing firms hold both accreditations.