How Much Does Penetration Testing Cost in the UK in 2026?

A penetration test in the UK costs between £1,500 and £5,000 for a basic external infrastructure test on a small business, rising to £20,000 or more for large organisations with complex environments or compliance-driven requirements.

The single biggest factor in pen test pricing is scope specifically, how many systems are being tested, whether the test is external or internal, and what level of accreditation the report needs to satisfy.

This guide gives you realistic UK pricing by test type, explains what drives costs up, and helps you decide what your business actually needs.

UK Penetration Testing Costs by Test Type — 2026 Pricing

These are realistic UK market rates for 2026. Day rates for CREST-certified testers run from £1,000 to £1,500 per tester per day, with most engagements taking between three and ten days depending on scope.

What Drives the Cost of a Penetration Test in the UK

Scope and number of systems. The most significant cost driver is how many assets are in scope. A test covering one external IP address is fundamentally different from a test covering fifty internal servers, multiple web applications, and cloud infrastructure. Every additional system adds tester time.

External vs internal testing. External tests target internet-facing systems and are typically faster to scope and execute. Internal tests require physical or VPN access, deeper analysis of internal architecture, and testing for lateral movement, all of which take longer and cost more.

CREST accreditation. If your organisation needs the test to satisfy PCI DSS requirements, ISO 27001 audit evidence, or cyber insurance renewal, you will need a CREST-certified provider producing a formally structured report. CREST-accredited testing commands a premium over uncertified testing, and rightly so, the methodology, quality of findings, and remediation guidance are significantly more rigorous.

Compliance-driven testing. Businesses working toward PCI DSS compliance or ISO 27001 certification need penetration testing that follows specific methodologies and produces documentation in a format the certification body or QSA will accept. This scoping requirement adds time and cost compared to a general security review.

Remediation retesting. Many businesses budget for the initial test but forget that remediation retesting, confirming that identified vulnerabilities have actually been fixed, is a separate engagement. For compliance purposes, retesting is often required before a certificate of compliance can be issued.

Penetration Testing vs Vulnerability Assessment, Understanding the Cost Difference

One of the most common questions UK businesses ask before buying is the difference between a penetration test and a vulnerability assessment. Understanding this distinction directly affects what you pay and what you get.

A vulnerability assessment is an automated scan that identifies known weaknesses in your systems. It is faster, less expensive, typically £500 to £2,000, and produces a list of vulnerabilities ranked by severity. It does not attempt to exploit them.

A penetration test goes further. A skilled tester actively attempts to exploit identified vulnerabilities, chains multiple weaknesses together, and demonstrates the real-world impact of a successful attack. It requires significantly more tester time and expertise, which is why costs are higher.

For most UK businesses, identifying weaknesses before attackers do requires both, a vulnerability assessment to build an ongoing picture of the estate, and an annual penetration test to validate that the most significant risks have been properly addressed. A good security partner will help you understand which is appropriate for your current maturity level and compliance obligations.

How Penetration Testing Frequency Affects Annual Budget

A single pen test is not a permanent green light. The UK Government Cyber Security Breaches Survey 2025 confirmed that 12% of UK businesses carried out penetration testing in the past year, but the businesses with the strongest security postures treat it as an annual programme, not a one-off event.

New vulnerabilities are discovered constantly. Every time you add a new application, change your network architecture, move to the cloud, or onboard a new third-party supplier, your attack surface changes. A test that was accurate in January may not reflect your risk in October.

Most UK businesses with compliance obligations, PCI DSS, ISO 27001, or Cyber Essentials Plus, are required to test at minimum annually. Many test every six months after significant infrastructure changes.

When budgeting pen testing annually rather than reactively, most providers offer a reduced rate for repeat engagements, typically 10 to 20 percent below the initial test cost, because the scoping work has already been done.

What to Look For When Choosing a Penetration Testing Company

Not all penetration testing providers in the UK are equivalent. Choosing the right penetration testing company for your organisation is one of the most important decisions in your security programme, and price alone is a poor guide.

The key things to verify before engaging a provider are CREST membership or CHECK scheme certification for government work, verifiable experience in your specific test type, web application testing requires different expertise from network testing, and a clear methodology that explains what will be tested, how, and what the deliverables look like.

A provider who cannot clearly explain their testing methodology before you sign a contract is a provider worth avoiding, regardless of price. The cheapest pen test in the market is rarely the one that finds the vulnerabilities that matter.

Annual Pen Testing Budget by Business Size

Small business, 1 to 50 staff: £2,000 to £8,000 per year

At this size, an annual external network test and a web application test covering your primary digital assets covers the most critical attack surface. If you are pursuing Cyber Essentials Plus, the technical audit is included in that cost.

Medium business, 50 to 200 staff: £8,000 to £20,000 per year

At this size, internal network testing becomes important alongside external and web application tests. Businesses with PCI DSS or ISO 27001 obligations need to ensure their pen test methodology and reporting format satisfy the specific requirements of those standards.

Large business, 200+ staff: £15,000 to £50,000+ per year

Organisations at this scale commission multiple penetration tests each year. Red team engagements simulate advanced multi-stage attacks. Cloud security testing and social engineering assessments are standard at this level.

Frequently Asked Questions

How much does a basic pen test cost for a UK small business? 

A basic external network penetration test for a UK small business with a limited internet-facing footprint costs between £1,500 and £3,500. Adding a web application test for one or two applications typically brings the total annual cost to £3,000 to £6,000.

Do I need CREST-certified penetration testing? 

CREST-certified penetration testing is recommended for compliance with PCI DSS, ISO 27001, or Cyber Essentials Plus. For general security assurance without compliance needs, non-CREST providers may be sufficient, though quality varies.

How long does a penetration test take? 

Most penetration tests for UK SMEs take between three and seven working days of tester time. Larger or more complex engagements, internal network tests, cloud tests, or red team exercises, take longer. The timeline from scoping to final report delivery is typically two to four weeks.

How often should a UK business run penetration tests? 

At minimum annually. Businesses with PCI DSS or ISO 27001 obligations are typically required to test at least once per year as part of their compliance programme. Businesses that make significant changes to their infrastructure or applications should consider testing after those changes, not just on a calendar cycle.

What is the difference between a pen test and a red team exercise? 

A penetration test assesses specific systems for known vulnerabilities within a defined scope. A red team exercise targets objectives, using realistic methods over time to simulate real-world attacks.

Can penetration testing be used for cyber insurance purposes? 

Yes. Many UK cyber insurers now ask for evidence of recent penetration testing as part of the renewal process. A test conducted by a CREST-accredited provider, with a formal report showing remediation of high and critical findings, carries the most weight with underwriters.