SOC 2 vs ISO 27001: Which Framework Should SaaS Companies Start With?

If you're a SaaS company starting to think seriously about security compliance, you're almost certainly looking at SOC 2 and ISO 27001. Both are widely recognised, both demonstrate security maturity to enterprise buyers, and both require a significant investment of time and money to achieve.

But they're not interchangeable. They come from different regulatory traditions, serve different markets, and have meaningfully different audit processes. Choosing the right one to start with — or whether to pursue both — can save you months of rework.

At a glance: the key differences

What SOC 2 actually is

SOC 2 (System and Organisation Controls 2) is a framework developed by the American Institute of CPAs (AICPA). It defines five Trust Services Criteria (TSC): Security, Availability, Confidentiality, Processing Integrity, and Privacy.

Almost all SaaS companies pursuing SOC 2 start with the Security criterion only. The audit results in a written report — not a certificate — produced by an independent CPA firm. A Type I report confirms your controls were designed correctly at a point in time. A Type II report confirms those controls operated effectively over a period (typically 6–12 months) — this is the one enterprise customers usually require.

SOC 2 doesn't prescribe specific controls. Your auditor assesses whether your controls, whatever they are, satisfy the Trust Services Criteria. This flexibility is both a strength and a challenge: you have more room to design controls that fit your business, but less explicit guidance on what to implement.

What ISO 27001 actually is

ISO 27001 is an international standard published by the International Organisation for Standardisation (ISO) and the International Electrotechnical Commission (IEC). The current version is ISO/IEC 27001:2022.

ISO 27001 certification requires you to establish, implement, maintain, and continually improve an Information Security Management System (ISMS). The standard defines mandatory requirements (Clauses 4–10) and 93 optional controls in Annex A that you must evaluate for applicability in a Statement of Applicability.

Unlike SOC 2, ISO 27001 results in a certificate issued by an accredited certification body (CB). The certificate is valid for three years, with mandatory annual surveillance audits. It's globally recognised and increasingly required for selling to European enterprise customers, government, and regulated industries.

Market and buyer expectations

SOC 2 is the dominant security compliance signal in the North American SaaS market. US enterprise security teams expect it. If your primary customers are US-based SaaS buyers, SOC 2 Type II is probably the minimum acceptable credential.

ISO 27001 is more widely required in Europe and APAC. European enterprise procurement processes — especially in financial services, healthcare, and government — routinely require ISO 27001 certification or equivalent. It's also increasingly required in the Middle East and parts of Asia.

If you're a European SaaS company selling to European enterprise customers, ISO 27001 is likely the better starting point. If you're a US-focused company, SOC 2 probably has more immediate sales impact.

If you're selling internationally, you'll likely need both eventually.

Audit process and timeline comparison

SOC 2 audit process: 1. Define your system description and scope. 2. Select a CPA firm. 3. Design and implement controls (3–6 months for a first-time company). 4. Type I audit: auditor assesses control design at a point in time. Takes 4–8 weeks. 5. Type II observation period: 6–12 months of operating the controls. 6. Type II audit and report: 6–10 weeks.

Total time to Type II: typically 9–18 months from start to report.

ISO 27001 audit process: 1. Define ISMS scope and conduct risk assessment. 2. Implement controls and documentation (6–12 months for a first-time company). 3. Internal audit. 4. Management review. 5. Stage 1 audit (document review): 1–2 days. 6. Remediation of any major nonconformities. 7. Stage 2 audit (implementation verification): 2–5 days depending on scope. 8. Certification decision: typically issued 2–4 weeks after stage 2.

Total time to certificate: typically 9–18 months from start to certificate.

Controls overlap: don't start from scratch twice

SOC 2 and ISO 27001 have significant controls overlap. If you build a solid security programme for one, you'll have most of the foundation for the other.

The largest overlaps are in: - Access control (user provisioning, MFA, privileged access, access reviews) - Incident management - Vulnerability management - Change management - Vendor and supplier management - Business continuity and backup

The key difference is documentation rigour. ISO 27001 requires a formal ISMS with documented policies, procedures, risk assessments, and management reviews. SOC 2 cares about whether controls operate effectively — less about the paperwork scaffolding.

If you start with ISO 27001, you'll have strong documentation that makes a subsequent SOC 2 audit significantly easier. If you start with SOC 2, you'll have operational control evidence but will likely need to invest in formal ISMS documentation to get to ISO 27001.

Which should SaaS companies start with?

Start with SOC 2 if: - Your primary customers are in North America. - Your sales cycles are being blocked by security questionnaires asking for SOC 2. - You want faster time-to-credential (Type I in 3–6 months from start). - You prefer a flexible, controls-based approach with less documentation overhead.

Start with ISO 27001 if: - Your primary market is Europe or APAC. - You're selling to government, financial services, or healthcare customers. - You want a globally recognised certificate rather than a US-centric report. - You're building for the long term and want a systematic ISMS rather than a point-in-time audit.

Start with both if: - You're fundraising or running a competitive sales process where both are expected. - You have the resources to run both programmes in parallel. - Your customer base is genuinely international.

The good news: if you use a platform like Certvik to automate evidence collection and control monitoring from the start, the incremental work to add a second framework is much lower than starting each one from scratch.

Cost considerations

Neither framework is cheap. Beyond the audit fee itself, factor in:

• Internal time: 200–500 hours for a first-time SOC 2; 300–800 hours for a first-time ISO 27001, depending on organisation size and starting maturity.
• Tooling: compliance platforms, vulnerability scanners, MDM, endpoint detection.
• Remediation: fixing the gaps you discover during prep — this is often where the real cost lies.
• Ongoing maintenance: SOC 2 Type II requires continuous control operation; ISO 27001 requires annual surveillance audits.

A rough total cost of ownership for a first-time compliance effort (Year 1, including audit, tooling, and internal time) is typically:

• SOC 2 Type II: $50,000–$150,000
• ISO 27001: €30,000–€100,000

These ranges are wide because company size, technical debt, and existing security maturity vary enormously.