ISO/IEC 27001 vs SOC 2: Certification or Attestation, Controls, Cost, and Which One You Need
The core difference is what you walk away with: ISO/IEC 27001 is an international standard you get certified against by an accredited certification body, while SOC 2 is an independent examination by a licensed CPA firm that produces an attestation report, not a certificate. ISO 27001 is the dominant credential for global and EU/UK enterprise deals; SOC 2 is the default for US and North American B2B SaaS. If your buyers are international, lean ISO 27001; if they are US enterprises sending vendor security questionnaires, they are usually asking for SOC 2 — and many companies end up needing both.
ISO/IEC 27001 vs SOC 2 at a glance
| ISO/IEC 27001 | SOC 2 | |
|---|---|---|
| Type | Certifiable international standard for an Information Security Management System (ISMS) | Attestation report on controls — a report, not a certificate |
| Issued / verified by | Accredited certification body (e.g. UKAS- or ANAB-accredited), after a Stage 1 + Stage 2 audit | Independent licensed CPA firm, under the AICPA's SSAE 18 (AT-C 205) attestation standard |
| Underlying standard | ISO/IEC 27001:2022 (requirements in clauses 4-10, plus Annex A reference controls) | AICPA Trust Services Criteria, examined under the SSAE 18 attestation standard |
| Controls | 93 reference controls in Annex A (37 Organizational, 8 People, 14 Physical, 34 Technological); you select the applicable ones and justify each inclusion or exclusion in a Statement of Applicability | No fixed control list — you design your own controls mapped to the five Trust Services Criteria categories (Security is mandatory; Availability, Confidentiality, Processing Integrity, and Privacy are optional) |
| Geography / recognition | Globally recognized; the leading credential outside North America (EU, UK, APAC, global enterprise) | Predominantly US and North American, though increasingly recognized internationally; the default ask in US enterprise procurement |
| Validity & renewal | Certificate typically valid ~3 years, with annual surveillance audits and recertification at the end of the cycle | Report covers a single point in time (Type I) or an observation window of roughly 3-12 months (Type II); typically renewed with a new Type II each year |
| Best for | Companies selling to international or EU/UK enterprises, or that want a recognizable certificate to display | US/North American B2B SaaS, cloud platforms, and service organizations whose deals stall in vendor security review |
| Indicative cost (audit/exam only) | ~$5,000-$15,000+ for an SME (Stage 1 + Stage 2), plus documentation and implementation effort | ~$5,000-$60,000+ for the CPA examination depending on scope and report type, plus readiness work |
Key differences
The deepest difference is the deliverable and who stands behind it. ISO/IEC 27001 results in a certificate issued by an accredited certification body that audits a working ISMS against the standard's clauses and the Annex A controls you selected, whereas SOC 2 produces an attestation report written and signed by a licensed CPA firm about controls you designed yourself against the AICPA Trust Services Criteria. That drives the second difference: ISO 27001 gives you a fixed catalogue of 93 reference controls to choose from and a Statement of Applicability to justify inclusions and exclusions, while SOC 2 prescribes criteria but no enumerated control list, so two SOC 2 reports can describe very different control sets. The third is reach — ISO 27001 is the international lingua franca of security trust, while SOC 2 is the credential US enterprise buyers most often demand. Importantly, the two overlap heavily at the control level (access control, change management, incident response, risk assessment, vendor management), which is why a single, well-built program can support both.
Which should you choose?
Choose ISO/IEC 27001 if you sell into international, EU, or UK markets, if RFPs ask for a recognizable certificate, or if you want a structured management system you can mature over time. Choose SOC 2 if your buyers are US or North American enterprises whose security teams send vendor questionnaires and expect a current SOC 2 report — usually a Type II — before they sign. Because the underlying controls overlap so much, a large share of growing SaaS companies pursue both: run one security program, then satisfy the ISO audit and the SOC 2 examination from the same set of policies and evidence. Whichever path you take, editable policy toolkits accelerate the documentation — often the most time-consuming step — but the certificate or the report still comes only from the accredited certification body or the CPA firm.
Recommended toolkits
ISO 27001 + SOC 2 Dual Toolkit
47 documents covering both frameworks plus a control crosswalk, risk register, Statement of Applicability and TSC mapping — run one security program, pass two audits.
ISO 27001 Complete Toolkit
All 24 policies and procedures plus the risk register, 93-control Statement of Applicability and audit evidence checklist — audit-ready from day one.
SOC 2 Complete Toolkit
22 policies plus the risk register, full Trust Services Criteria mapping and audit evidence checklist — built for startups facing their first SOC 2.
Frequently asked questions
- Is SOC 2 a certification?
- No. SOC 2 is an attestation report issued by a licensed CPA firm, not a certification, and there is no certifying body. Saying you are "SOC 2 certified" is technically incorrect — the accurate phrasing is that you have completed a SOC 2 examination or have a SOC 2 (Type I or Type II) report. ISO/IEC 27001 is the framework here that actually leads to a certificate, issued by an accredited certification body.
- Do I need both ISO 27001 and SOC 2?
- Often, if you sell internationally and into the US. ISO 27001 is the recognized credential for EU, UK, and global enterprise buyers, while SOC 2 is what US enterprise procurement typically requests. The two share most underlying controls, so many companies build one program and satisfy both — which is why a combined toolkit and control crosswalk can be more efficient than maintaining two separate efforts.
- Which is harder or more expensive, ISO 27001 or SOC 2?
- It depends on scope, not the framework alone. ISO 27001 requires a documented management system, a Statement of Applicability covering all 93 Annex A controls, internal audits, and a two-stage certification audit. SOC 2 requires controls mapped to the Trust Services Criteria and, for a Type II, an observation window of roughly 3-12 months before the CPA examination. Audit and exam fees overlap broadly (often five figures for a small company), and most of the cost and time in either case is the readiness and documentation work that precedes the audit.
- Will buying a policy toolkit make me ISO 27001 certified or give me a SOC 2 report?
- No. Editable toolkits give you the policies, procedures, risk register, Statement of Applicability, and Trust Services Criteria mapping that auditors expect to see, which removes weeks of drafting. They accelerate readiness, but certification still requires an accredited certification body to audit your live ISMS, and a SOC 2 report still requires an independent CPA firm to examine your controls.