Penetration Testing Cost UK: 2026 Pricing Guide

The single most common question we get before a scoping call: “How much does a penetration test cost in the UK?” The honest answer is that it depends, but there are clear benchmarks, and this guide gives you all of them so you can budget accurately and avoid being overcharged or under-tested.

Penetration testing cost in the UK ranges from around £3,000 for a small-scope external infrastructure or phishing engagement to £75,000 or more for threat-intelligence-led red teaming aligned to STAR and TIBER-UK structures. The variance is real and driven by scope, not just vendor margin. Understanding what drives the cost helps you scope your engagement correctly, and avoid paying for testing depth you don’t need, or skimping on depth you do.

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

Most standard UK application, API and cloud security penetration tests land in the £6,000 to £18,000 range in 2026. EJN Labs prices start at £5,000 for a small web application test, £4,500 for a single-platform cloud security review and £3,500 for a small external infrastructure test. Every figure is a scope-based fixed price agreed before work starts, not a day rate multiplied by a day count.

Red teaming sits outside that band, from £15,000 for a focused engagement to £75,000 or more for threat-intelligence-led red teaming aligned to STAR and TIBER-UK structures. The table below breaks down our published UK prices by test type.

Penetration Testing Cost UK: Quick Reference

Test Type	Published Price Range	Duration	What’s Included
Web Application	£8,000–£18,000	6–12 days	OWASP Top 10, business logic, complex auth flows, API endpoints
Mobile Application (iOS or Android)	£7,500–£14,000	5–10 days	OWASP Mobile Top 10, traffic interception, binary analysis, storage testing
API Penetration Testing	£7,000–£12,000	4–9 days	OWASP API Top 10, authentication, rate limiting, authorisation
Cloud Security Review (single platform)	£8,000–£14,000	4–5 days	IAM, storage, compute, network configuration review and exploitation
External Infrastructure	£6,500–£12,000	3–5 days	Port scanning, service enumeration, vulnerability exploitation, reporting
Internal Network (up to ~150 hosts)	£1,200–£3,600	1–3 days	Lateral movement, AD attacks, privilege escalation, segmentation testing
VAPT (vulnerability assessment plus pen test)	£7,000–£12,000	3–5 days	Compliance baseline evidence for ISO 27001, PCI DSS and SOC 2
Secure Code Review	£7,000–£12,000	4–7 days	Pre-release source review, 2,000 to 4,000 LOC, one or two languages
AI and LLM Penetration Testing	£6,000–£12,000	5–7 days	Prompt injection, RAG pipeline abuse, agent and tool misuse
Phishing and Social Engineering	£6,000–£15,000	7–10 days	Spear phishing simulation, click rates, credential capture, reporting
Red Team Exercise (focused)	£15,000–£35,000	2–3 weeks	Assume breach, phishing, physical, C2, full attack simulation
Cyber Essentials Plus	£1,200–£3,500	5–15 days	Assessor-led hands-on verification of the five CE controls (not a pen test)

For detailed scope and pricing by test type, see our dedicated guides: web application, API, external infrastructure, cloud and red teaming testing, or view our full pricing guide. For typical day counts per engagement type, see how long a penetration test takes. All EJN Labs testing is delivered by our CREST-accredited UK team.

These are the prices EJN Labs publishes. Every one is a scope-based fixed price for a defined scope, agreed after a 30-minute scoping call and fixed once the statement of work is signed. We do not bill day rates to clients, so no price here is a day rate multiplied by a day count.

Penetration Testing Cost by Service

Each test type has its own cost drivers, so we publish a dedicated 2026 price guide for every service. Pick the one that matches the engagement you are scoping:

• Web Application Penetration Testing Cost UK (2026 Guide): pricing by complexity tier, user roles and authentication depth.
• API Penetration Testing Cost UK (2026 Pricing Guide): pricing by endpoint count, authentication flows and documentation quality.
• Mobile App Penetration Testing Cost UK (iOS and Android, 2026): platform pricing, MASVS levels and why the backend API is a separate scope.
• Network Penetration Testing Cost: Internal vs External Pricing (UK 2026): host counts, Active Directory complexity and segmentation testing.
• Cyber Essentials Cost Breakdown for Small Businesses: the fixed certification fee, the Plus audit fee and the hidden costs to budget for.
• Fixed-Price vs Day-Rate Penetration Testing: what the UK day rate buys and which billing model protects your budget.
• DSPT Penetration Testing Cost UK (2026 Guide): fixed-price scoping and what the toolkit expects by organisation type.
• PCI DSS Penetration Testing Cost UK (2026 Guide): per-requirement pricing against 11.4.1 to 11.4.6.

What Drives Penetration Testing Costs in the UK

1. Scope and Complexity

The most significant cost driver. “Test my web application” means nothing without knowing: how many distinct roles/user types exist (each adds testing time), whether the application has complex business logic that requires manual testing rather than automated scanning, how many endpoints/functions need to be exercised, and whether authentication mechanisms are standard (OAuth, SAML) or bespoke.

A well-scoped engagement starts with a call where the testing team asks detailed questions about your application’s architecture. Any firm quoting without this conversation is guessing at scope, and will either over-charge or under-test.

2. CREST Certification

Testing from a CREST-accredited provider costs more in the UK than testing from an unaccredited one. That gap reflects the cost of maintaining company accreditation, the market rate for CREST-certified testers, and the quality assurance processes CREST sets out. For regulated industries (financial services, healthcare, government), CREST accreditation is often a procurement requirement for buyers, not a nice-to-have. For unregulated businesses, it’s still a meaningful quality signal: CREST exams are technically rigorous, and the company accreditation verifies insurance, professional standards, and quality controls.

3. Testing Approach (Black, Grey, or White Box)

Black box testing (where the tester receives no prior knowledge and begins with only a URL or IP range) takes longer because reconnaissance is included in the engagement. White box testing, where the tester receives architecture documentation, source code access, and user credentials, is typically faster and more thorough for the same budget. Grey box (credentials but no source code) is the most common approach and represents a good balance for most engagements.

4. Report Quality and Compliance Requirements

Basic vulnerability scanning reports cost less but carry less value. A full penetration test report includes: executive summary for non-technical stakeholders, technical findings with reproduction steps and screenshots, CVSS v3.1 severity scoring, remediation guidance with specific code or configuration changes, risk register alignment, and compliance mapping (PCI DSS, ISO 27001, SOC 2 control references). If your regulator or auditor has specific reporting requirements, a good testing firm will align the format at the scoping stage; add 10–20% to account for custom reporting.

5. On-Site vs Remote Testing

Most penetration testing is conducted remotely. Internal network tests can be performed remotely via a VPN jumpbox or through a laptop deployed on-site. If you require testers on-site (for physical penetration testing, air-gapped environments, or wireless security assessments) most firms price on-site work above remote work and add travel. EJN Labs quotes on-site work inside the fixed price agreed at scoping, with no callout or out-of-hours fees, and offers next-business-day on-site cover in London and Canary Wharf.

6. Retesting

A penetration test without a retest only tells you what was broken before you fixed it. Retesting verifies that remediation is effective and that the fixes haven’t introduced new vulnerabilities. Most firms include one retest pass in the engagement cost, or offer it as an add-on at roughly 20–30% of the original test cost.

Pentesting Cost UK: Fixed Price vs Day Rate

UK penetration testing firms typically price in one of two ways:

Fixed-Price Engagements

More common for well-defined scopes (a specific web application, a defined IP range). You pay a fixed fee for a defined scope and deliverable. Risk of scope creep sits with the testing firm. Good for budget predictability. Requires accurate scoping upfront, if the scope turns out to be larger than agreed, there may be overage charges or reduced testing depth.

Day-Rate Engagements

More common for complex or open-ended testing (red teams, novel attack surfaces, unknown scope). UK day rates for CREST-certified testers sit at a fair-market £1,100 to £1,400 per day. EJN Labs publishes that band as a sanity-check on the market rather than as a billing basis: we quote a fixed price for a defined scope and do not bill day rates to clients. Day-rate engagements elsewhere give flexibility but require active scope management to avoid runaway costs. If you buy one, insist on a daily check-in and agreed testing priorities at the start of each day.

What is the day rate for penetration testing in the UK? UK day rates for CREST-certified testers sit at a fair-market £1,100 to £1,400 per day. EJN Labs does not bill day rates to clients: we publish that band so you can sanity-check our fixed prices against the broader UK CREST market, and every quote is a scope-based fixed price agreed before work starts.

All EJN Labs testing is delivered by UK-based, CREST-certified testers working under our CREST company accreditation. The price of a test is driven by the complexity of what is in scope, not by who is assigned to it. For a defined scope a fixed-price quote is usually better value than an open day rate.

Pen Test Costs UK: What Affects Your Final Invoice

Beyond the base engagement cost, watch for these line items that affect the final invoice:

• Scope changes mid-engagement: discovered during testing that the application is significantly larger than scoped. Address this by being thorough in scoping upfront.
• Emergency findings communication: critical vulnerabilities requiring out-of-hours calls. Good firms include this at no extra charge; verify in the contract.
• Executive presentation: some firms charge separately for presenting findings to the board or C-suite. EJN includes a findings walkthrough call in all engagements.
• Letter of attestation: a formal signed letter confirming testing was completed to a specified standard, sometimes required for compliance submissions. Usually included; confirm this.
• Raw findings data export: CSV or XML export of findings for import into your vulnerability management platform.

How to Get the Most Value From Your Penetration Testing Budget

1. Invest in scoping, not just testing: A 30-minute scoping call will prevent both over-spending on irrelevant test areas and under-spending on critical ones. Don’t skip it to save time.
2. Test what matters first: If budget is constrained, prioritise by risk: internet-facing applications and systems handling sensitive data before internal tooling.
3. Get a retest included: A test without retest verification is a snapshot, not an assurance. Negotiate retesting into the base contract.
4. Ask about findings during testing, not after: Firms that only deliver findings in the final report force remediation into a future sprint. Firms that report as they go let you fix critical issues while testing is still in progress.
5. Compare apples to apples: Ensure any quotes you’re comparing cover the same scope, testing approach, deliverables, and certification level. A £4,000 quote and a £9,000 quote for “the same test” are rarely for the same test.

Sample UK Pen Test Engagement: What Your Budget Buys

To make the numbers concrete, here is a typical mid-size engagement. A UK SaaS company commissions a grey-box test of its customer-facing web application (five user roles) plus the supporting API. Scope is agreed in a 30-minute call and lands in our published standard web application tier: £8,000 to £18,000 over an 8 to 12 day engagement, quoted as a single fixed price before any testing starts. The deliverable is a prioritised report mapped to the OWASP Top 10, a remediation plan, and a free retest once fixes are in place.

How to Buy a Pen Test in the UK: Buyer Checklist

• ☐ Confirm the testers are CREST-certified and UK-based.
• ☐ Get a fixed-price quote against a written scope, not an open-ended day rate.
• ☐ Check whether a retest after remediation is included or charged separately.
• ☐ Ask which frameworks the report maps to (OWASP, ISO 27001, SOC 2, Cyber Essentials).
• ☐ Confirm the report is suitable for auditors and customers, not just an internal scan dump.
• ☐ Be wary of quotes far below the ranges above; cut-price testing usually means automated scanning, not manual exploitation.

Frequently Asked Questions

How much does a web application penetration test cost in the UK?
Our published standard tier for a multi-role SaaS web application is £8,000 to £18,000, quoted as a fixed price for a defined scope by our CREST-accredited UK team. A small single-role application sits in the £5,000 to £8,000 tier. A multi-tenant enterprise application with complex authentication sits in the £18,000 to £35,000 tier.

Why is CREST-accredited penetration testing more expensive?
CREST accreditation requires investment in tester training and examination, company-level quality controls, professional indemnity insurance at a specified level, and ongoing accreditation maintenance. This overhead is reflected in pricing and represents genuine value: CREST exams are technically rigorous, and accreditation verifies the firm operates to a professional standard.

Can I get penetration testing under £2,000?
Yes, for very small, well-defined scopes (a landing page or brochure site with no user authentication, a single API endpoint), some firms will price below £2,000. Be cautious: penetration testing below this threshold typically involves minimal manual effort and heavy reliance on automated scanning, which misses business logic vulnerabilities. For anything handling user data or financial transactions, this level of testing is insufficient.

Is penetration testing a tax-deductible business expense in the UK?
Generally yes, penetration testing is a business expense related to cybersecurity and IT security management. It typically qualifies as a deductible revenue expenditure. Consult your accountant for advice specific to your circumstances.

How often should UK businesses do penetration testing?
PCI DSS Requirement 11.4.3 requires external penetration testing at least once every 12 months and after significant change. ISO 27001 and SOC 2 do not require a penetration test at all and set no frequency, though auditors for both commonly expect one as evidence. FCA-regulated firms and organisations with rapid development cycles typically test more frequently, quarterly for critical applications or after major releases. See our penetration testing checklist for a full readiness guide.

How much should a penetration test cost?
A penetration test should cost enough to fund hands-on manual testing by a CREST-certified tester. Most standard UK application, API and cloud security tests land in the £6,000 to £18,000 range. If a quote is far below the published range for that scope it usually reflects automated scanning rather than hands-on exploitation, which auditors and attackers both see through.

How much does a typical penetration test cost in the UK?
A typical UK penetration test costs £6,000 to £18,000: a multi-role web application, API or cloud security review delivered by our CREST-accredited UK team as a scope-based fixed price, with a remediation plan and a free retest included.

What is the day rate for penetration testing in the UK?
UK day rates for CREST-certified testers sit at a fair-market £1,100 to £1,400 per day. EJN Labs does not bill day rates to clients: we publish that band purely so you can sanity-check our fixed prices against the wider UK CREST market. Every engagement is quoted as a scope-based fixed price.

What affects the price of a penetration test?
Scope and complexity, whether the provider is CREST-accredited, the testing approach (black, grey or white box), report quality and compliance needs, on-site versus remote work, and whether a retest is included. EJN Labs includes free retests and fixed pricing, so the quote is the final cost.

Choosing between firms? See why EJN Labs is the best UK penetration testing provider, or explore penetration testing as a service for ongoing coverage.

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