ISO 27001 is the international ISMS standard — globally recognised, certifiable, prescriptive about a management system. SOC 2 is a US-origin AICPA attestation report covering five Trust Services Criteria; it produces a report, not a certificate.
Any organisation worldwide — strongest recognition in EU, UK, APAC and government tenders.
SaaS and B2B technology vendors — strongest recognition in the United States. Required by most US enterprise buyers.
All ten dimensions head-to-head:
| Aspect | ISO 27001 | SOC 2 |
|---|---|---|
| Output | Certificate (3-year, with surveillance) | Attestation report (Type I or Type II) |
| Issued by | Accredited certification body | Licensed CPA firm |
| Geographic recognition | Global | Primarily United States |
| Framework | 93 Annex A controls, ISMS-driven | 5 Trust Services Criteria (Security required + 4 optional) |
| Type I vs Type II | Not applicable | Type I = point-in-time; Type II = 6–12 months operating effectiveness |
| Standardised report? | Yes (certificate) | No — each CPA firm produces a custom report |
| Customer due-diligence | Share certificate + SOA | Share full SOC 2 report under NDA |
| Frequency | Annual surveillance, 3-yearly re-cert | Typically annual (Type II) |
| Cost (SME) | £15k–£40k first year | $25k–$80k first year (US firms) |
| Time to achieve | 6–12 months | Type I: 2–3 months; Type II: 9–18 months |
Choose ISO 27001 if your buyers are in EU, UK, APAC; if you tender for government work; if you want a portable single-page certificate to show prospects.
Choose SOC 2 if your buyers are US enterprises; if you’re a SaaS vendor with US revenue; if you need a detailed evidence-of-control report (not just a certificate).
Many global SaaS vendors hold BOTH — ISO 27001 for non-US buyers + SOC 2 Type II for US enterprise sales. The overlap is ~80%, so the second is significantly cheaper than the first.
They’re comparably rigorous but emphasise different things. ISO 27001 demands a management system (PDCA, risk assessment, ISMS scope). SOC 2 Type II demands operating-effectiveness evidence over a 6–12 month window.
If you sell SaaS to US enterprises and non-US buyers, often yes. The control overlap is high so the marginal cost of the second is much lower.
No — it’s an attestation. Your CPA firm issues a report stating an opinion on your controls. There is no SOC 2 certificate.
SOC 1 covers financial reporting controls. SOC 2 covers Trust Services Criteria (security, availability, confidentiality, processing integrity, privacy). SOC 3 is a public-facing summary of SOC 2.
In US markets often yes. Outside the US, ISO 27001 is more widely recognised in tenders and contracts.
Both standards have free interactive gap-analysis tools — no sign-up, no install.