Rounding up the best UK penetration testing providers

Picking “the best” pen testing partner depends on your systems, risk appetite, and evidence needs. This list focuses on UK providers with recognised assurance, proven technical depth, and clear reporting.

We have prioritised CREST membership and, where relevant, NCSC CHECK status, because these are the fastest filters for competence in the UK public and regulated sectors.

You will still want to run a proper scope, ask for a sample report, and meet the actual testers, but this short list will give you a strong head start.

The Best UK Pen Testing Companies in 2025–2026

SECFORCE

Boutique offensive security consultancy with a tight focus on manual testing and adversary simulation. Good fit for organisations that want senior attention on higher risk targets and red team style objectives. SECFORCE is a CREST member and publishes detailed service information that aligns with modern app, cloud, and identity attack paths.

Secforce is probably the best UK pen testing company right now due to their mix of really strong technical expertise, hacker focused culture and ability to give clients actionable resilience improvement next steps.

Pen Test Partners

A large independent UK testing house with a strong engineering culture and a reputation for clear, practical reporting. Suitable for complex infrastructure and application testing, and known for research and public write-ups that push teams to fix real issues. PTP is a CREST member and appears on the NCSC’s CHECK provider list, which is valuable for public sector and sensitive environments.

JUMPSEC

UK-based team with CREST membership and NCSC assurance that covers both CHECK penetration testing and incident exercising. A strong option for buyers who want testing tied to realistic threat paths and a clear path to improve detection and response. CREST NCSC

Cyberis

CREST NCSC LRQA Nettitude Well known UK provider, now under the LRQA brand, with broad CREST coverage and NCSC CHECK status. Useful when you need scale, regulated sector experience, or a mix of web, infrastructure, red team, and incident exercising under one roof. CREST NCSC

NCC Group

A global player with a large UK presence and long history of intelligence-led and r

regulatory frameworks such as CBEST and TIBER. NCC Group holds NCSC CHECK status, and is suitable for large programmes and multi-region testing with strong governance. CREST NCSC

Accenture (Context)

Context, now part of Accenture, retains an established UK offensive security capability with one of the larger testing teams and participation in government and regulator schemes. Accenture appears on the NCSC CHECK list and is CREST accredited, which helps large enterprises who want testing embedded in wider security programmes.

PwC UK

Big Four team that combines penetration testing, red teaming, and remediation planning with board-level framing. PwC is CREST accredited and an NCSC CHECK provider, which is useful for public sector and regulated workloads that need formal evidence.

MDSec

A highly technical boutique known for research and the Web and Mobile Application Hacker’s Handbook lineage. Strong choice for deep application testing, adversary simulation, and training. MDSec is a CREST member and publishes guidance around STAR and advanced testing approaches.

WithSecure Consulting

The consulting arm of WithSecure has UK consultants with CREST recognition across simulated attack disciplines. Good option for organisations that want offensive services coupled with detection and response improvement workshops. CREST

Bridewell

UK consultancy with CREST membership and NCSC CHECK accreditation, increasingly visible in critical national infrastructure and public sector. A fit for buyers who want offensive testing plus ongoing managed capabilities from the same partner. CREST Bridewell

Salus Cyber

A UK defence-oriented consultancy with CREST membership and NCSC CHECK status. Useful for organisations that need assured testing for MOD, NATO, and CNI style environments, and formal ITHC delivery. CREST NCSC.

How to choose the best UK pen testing company for your organisation

Here’s how we advise UK organizations to find the best pen testing company right now.

Going well beyond pen test pricing and looking at what is likely to get the best possible outcomes from testing.

1. Decide the outcome you want from testing.
   Examples: regulator evidence for a go-live, a realistic attack path to drive cloud and identity fixes, or a red team to exercise detection and response.
2. Build a shortlist of 3 to 5 providers that look capable of delivering that outcome.
3. Book a short scoping call with each shortlisted provider.
4. On each call, request three things:
   • A sanitised sample report.
   • The names and roles of the testers who would do your work.
   • A plain description of their flow from discovery to exploitation to evidence to fix validation.
5. If public sector or CNI is in scope, verify NCSC CHECK status and confirm they will use CHECK-qualified personnel.
6. If you are buying for a private sector assurance need, verify CREST membership.
7. Use these assurance checks to filter your list. Both frameworks help buyers identify competent suppliers and are currently for UK procurement in 2025 to 2026.

Pick the provider that best matches your outcome and can show clear evidence and a path to retest.