The verdict in three sentences
A security audit coupled with an external pentest costs between 5,000 and 20,000 EUR in 2026 depending on your application's attack surface. An internal audit catches misconfigurations, but only a third-party pentest is recognised by an enterprise client or an ISO 27001 auditor. Budget 2 to 4 weeks of testing, a prioritised remediation report and an included retest to validate the fixes.
Internal audit or external pentest: which to choose
Internal audits (code review, automated scanning, configuration review) are useful continuously but do not replace a pentest. A pentest simulates a real attacker across the OWASP Top 10: injection, broken authentication, data exposure, broken access control. For a CIO preparing a certification or answering a client security questionnaire, the required deliverable is a dated, third-party-signed pentest report.
| Test type | Scope | 2026 cost (EUR) | Timeline |
|---|---|---|---|
| Automated scan (SAST/DAST) | Known vulnerabilities | 800 - 2,500 | 3 - 5 days |
| Configuration audit | Server, headers, TLS | 1,500 - 4,000 | 1 week |
| Grey-box pentest (web app) | Authenticated OWASP Top 10 | 5,000 - 12,000 | 2 - 3 weeks |
| Full black-box pentest | App + API + infra | 12,000 - 20,000 | 3 - 4 weeks |
| Remediation retest | Fix verification | Included - 1,500 | 3 - 5 days |
The real cost: test, fix, then maintain
The pentest is only the first budget line. Fixes depend on the findings: a broken access control is fast to correct, while reworking session management costs more. Then plan for security maintenance covering dependency updates and CVE monitoring.
| Line item | 2026 range (EUR) | Frequency |
|---|---|---|
| Initial web app pentest | 5,000 - 12,000 | One-off / annual |
| Fixes (minor to major findings) | 3,000 - 15,000 | After audit |
| Validation retest | 0 - 1,500 | After fixes |
| Security maintenance (patches, CVE watch) | 300 - 800 / month | Recurring |
| EV SSL cert + managed WAF | 40 - 200 / month | Recurring |
Mini case study
Mark, CIO of a 45-person SaaS SME in London, must provide a pentest report to an enterprise client before signing a contract worth 180,000 EUR/year. He orders a grey-box pentest at 9,000 EUR, fixes 6 findings for 6,500 EUR, and gets an included retest. Total budget: 15,500 EUR, i.e. 8.6% of the annual value of the secured contract. The signed report unlocks the signature within three weeks: the return on investment lands in the first billing month.
FAQ
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How much does a web application pentest cost in 2026?
Between 5,000 and 12,000 EUR for a grey-box pentest covering the OWASP Top 10, and up to 20,000 EUR for a full app + API + infrastructure test.
Is the retest really included?
With most serious providers a fix-validation retest is included if remediation happens within 30 to 90 days; beyond that, expect 500 to 1,500 EUR.
How often should a pentest be repeated?
At least once a year, and systematically after any major change to the application or infrastructure. A monthly automated scan complements the setup between pentests.
Is a pentest required for ISO 27001 certification?
It is not strictly mandatory, but the auditor expects a documented penetration-testing process; an annual pentest report is the strongest evidence.
How much does ongoing security maintenance cost?
Security maintenance runs between 300 and 800 EUR/month depending on the stack, covering dependency updates, CVE monitoring and small fixes.
Let's scope your project. Share your stack, the number of exposed endpoints and your client-audit deadline, and we will scope an OWASP pentest with a remediation report and retest. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
