ISO 27001 vs SOC 2: which one first

They are different kinds of thing

SOC 2 is an attestation. A licensed CPA firm examines the controls you say you operate and issues a report describing what they tested and what they found. The report is long, detailed and shared under an agreement. There is no pass mark and no certificate.

ISO 27001 is a certification against a standard. An accredited body audits your information security management system, and if it holds up you receive a certificate valid for three years with surveillance audits in between. The certificate is a single page you can put on a website. The underlying requirement is a running management system with risk treatment, internal audit and management review, which is more organisational work than most teams expect.

Cost and effort compared

For a company of around fifty people, a first SOC 2 Type 2 typically lands somewhere between $25,000 and $85,000 all in, counting auditor fees, tooling, penetration testing and internal time. A first ISO 27001 certification for the same company typically lands between $25,000 and $90,000 on the same basis, with the certification body fee smaller than a CPA fee but the management system work larger. In year two the picture flips a little: ISO surveillance audits are cheaper than an annual SOC 2 examination, but the internal audit and management review cadence continues regardless.

Which buyers expect which

• Selling to United States technology companies: SOC 2, almost without exception. Many procurement teams will not recognise an ISO certificate as a substitute.
• Selling to European, Middle Eastern or Asian enterprises: ISO 27001 is the common currency and often appears in tender requirements as a hard gate.
• Selling to regulated industries: expect both, plus sector specific requirements such as HIPAA or PCI DSS on top.
• Selling to small businesses: often neither is required yet. Do not buy a framework before a deal asks for one.

The overlap, and what the second one costs

The two frameworks share a lot of evidence: access control, change management, logging, vendor management, training, incident response. Once you have done either properly, adding the second usually costs 40 to 60 percent of a standalone programme rather than a full second bill. Two things reduce that further. Use one auditor group that can cover both, so fieldwork happens once. And keep one control set mapped to both frameworks rather than running two parallel documentation stacks, which is the most common and most expensive mistake.

If you genuinely need both within a year, most teams find it cheaper to run readiness once for both, then take SOC 2 Type 1 early to unblock deals, then the ISO certification audit, then the SOC 2 Type 2 window. Sequencing matters more than the choice itself.

A simple rule

Pick the framework that unblocks revenue this quarter. Build the controls so the other one is a mapping exercise rather than a new project. Price both before you commit with the SOC 2 calculator and the ISO 27001 calculator, and use the readiness checklist as the shared evidence list for either route.