ISO 27001 vs SOC 2: Picking Your First Framework

"Should we do SOC 2 or ISO 27001?" is the wrong first question. The right one: "Who's asking, and what will they actually accept?"

Geography drives most of it

SOC 2 is an American instrument. AICPA-governed, dominated by US accounting firms, generally unfamiliar to European buyers. ISO 27001 is the global standard — expected throughout EU, UK, APAC, and increasingly in large US enterprises that want a universal yardstick.

If your first 10 customers are North American SaaS companies: SOC 2 first. If your pipeline leans European or multinational: ISO 27001 first.

Rigor and scope differ

SOC 2 is flexible. You define your controls, the auditor confirms they address the Trust Services Criteria. Two companies with identical SOC 2 reports might have very different control implementations.

ISO 27001 is more prescriptive. Annex A lists 93 specific controls (in the 2022 revision), and you either apply each one or document why it's not relevant via a Statement of Applicability. Less room for creativity, more signal for sophisticated buyers.

Audit rhythm differs

SOC 2 Type II covers a single observation period, with a new audit each year. ISO 27001 runs on a three-year certification cycle: a big Stage 1 + Stage 2 audit to certify, then two lighter surveillance audits, then recertification. ISO audits are generally more expensive but less frequent.

The practical answer

Most AI-native B2B SaaS companies should start with SOC 2 Type I if their buyers are North American, then add ISO 27001 as they expand internationally. The good news: there's ~60% control overlap, so once you've done one, the second is roughly 40% more work, not 100%.

What to avoid

Don't try to pursue both simultaneously as your first compliance effort. Context-switching between two audit teams will eat your quarter. Get one done, operationalize it, add the second when you have a business reason — not just because it sounds comprehensive.