SOC 2 is a CPA-issued attestation report favored by North American buyers; ISO 27001 is an international certification of your security management system, favored in Europe and Asia. The controls overlap heavily (completed SOC 2 work commonly pre-fills around 60% of ISO 27001), so the real question is usually sequencing, not either/or.
SOC 2 vs ISO 27001 comparison table
| Dimension | SOC 2 | ISO 27001 |
|---|---|---|
| Who asks for it | US and Canadian buyers, especially mid-market and enterprise SaaS customers | European, UK, and Asian buyers; global enterprises and public tenders |
| Issued by | A licensed CPA firm (AICPA attestation) | An accredited certification body |
| What you get | A detailed report (shared under NDA) with the auditor's opinion and tested controls | A certificate you can publish, plus surveillance audits |
| Structure | Trust Services Criteria: mandatory Security (CC1-CC9) plus optional categories; you define the controls | Management system clauses 4-10 plus Annex A: 93 reference controls in 4 themes; SoA declares applicability |
| Audit model | Type 1 (point in time) or Type 2 (3-12 month observation window), re-issued annually | Stage 1 + stage 2 certification, then annual surveillance, full recertification every 3 years |
| Typical audit fees | Type 1 $5k-$20k; Type 2 $12k-$40k+ per year | Commonly $10k-$30k across the initial 3-year cycle |
| Typical first-time timeline | Type 1 in 2-4 months; Type 2 commonly 4-9 months end to end | Commonly 4-8 months from a decent baseline to stage 2 |
| Mandatory extras | No internal audit requirement | Internal audit and management review are required before certification |
Which one do you need?
- Selling mostly to US companies? SOC 2. It is the default line item in North American vendor security reviews, and a Type 2 report answers most questionnaires. Start with the SOC 2 compliance checklist.
- Selling into Europe, the UK, or global enterprises? ISO 27001. The certificate is recognized worldwide, is often a hard requirement in EU procurement, and unlike a SOC 2 report you can display it publicly.
- Selling to both? You will eventually hold both, and the smart move is to plan them together from day one rather than running two sequential greenfield projects.
A useful tiebreaker when demand is genuinely mixed: SOC 2 Type 1 is the fastest credible artifact you can put in front of a buyer, so US-facing teams usually start there even when ISO 27001 is on the roadmap.
The ~60% overlap, concretely
Both frameworks are, underneath, asking for the same operational security program. Map them side by side and the overlap is unmistakable:
- SOC 2 CC6 (logical and physical access) covers the same ground as ISO 27001 Annex A's identity, access control, and physical controls: SSO, MFA, least privilege, provisioning, and revocation.
- SOC 2 CC3 (risk assessment) maps to ISO clauses 6.1 and 8.2: a documented, repeatable risk methodology with treatment decisions.
- SOC 2 CC7 (system operations) and CC8 (change management) map to Annex A's operations security, logging, and change controls.
- SOC 2 CC9 (vendor risk) maps to Annex A supplier relationship controls.
- Policies, security training, incident response, backups, and business continuity are required artifacts in both.
That is why completed SOC 2 work commonly pre-fills around 60% of an ISO 27001 program. The remaining ~40% is mostly ISO's management system machinery: a formally scoped ISMS, the Statement of Applicability across all 93 Annex A controls, a mandatory internal audit, and management reviews with minutes. Going the other direction, an ISO 27001 certificate leaves you with most of a SOC 2 control set and mainly adds the CPA firm's evidence sampling.
Doing both without doing everything twice
The failure mode is treating each framework as its own spreadsheet: two risk assessments, two access review schedules, two evidence folders, two sets of policy reviews. The fix is a single control set cross-mapped to both frameworks, so one quarterly access review satisfies SOC 2 CC6 and ISO 27001 Annex A simultaneously, and one piece of evidence is collected once and reused everywhere. Sequenced this way, teams commonly add the second framework for a fraction of the first one's effort: the incremental work is the delta, not a second program. Evidence reuse is the mechanism; the audit evidence examples guide shows how the same artifacts serve both auditors.
One boundary sentence, because both frameworks end in someone else's judgment: cross-mapping prepares you efficiently, but the CPA firm's opinion and the certification body's decision are theirs alone. Nothing here, and no software, guarantees either outcome.
One control set, two badges
Complies is built around exactly this model: a single control set cross-mapped across SOC 2, ISO 27001, GDPR, HIPAA, and PCI DSS, with per-framework readiness scores, so finishing SOC 2 visibly pre-fills your ISO 27001 progress instead of resetting it to zero. Evidence is collected once with owners and due dates and reused across frameworks. It is self-serve with published prices from $79 per month and no sales call. See how control mapping software handles the overlap, and get started with whichever framework your next deal is asking for.
RUN IT, NOT JUST READ IT
Turn this into tracked rows with owners
Everything in this guide becomes obligations, controls, and evidence with owners and due dates inside Complies, with a live readiness score on top. Plans from $79 a month, prices published.