ISO 27001 or SOC 2? A Guide for US Startups Selling in Europe
SOC 2 usually comes first if your buyers are mostly American, and ISO 27001 first if your pipeline is mostly European or you sell to multinationals that ask for it by name. Both prove security maturity, and much of the work overlaps, so the deciding factor is what your next customers will ask for.
The two differ in what they are, who issues them and how buyers read them. Here's how they compare and how to sequence them if you need both.
Vendors Covered in this Article
Disclosure: We may earn a commission if you buy through some links on this page. It doesn't change what we recommend.
What is the difference between ISO 27001 and SOC 2?
ISO 27001 is an international standard for an information security management system (ISMS). An accredited certification body audits you and, if you pass, issues a certificate. The certificate lasts for a defined cycle with periodic surveillance audits in between.
SOC 2 is an attestation report written by an independent CPA firm under AICPA criteria. It describes your controls and the auditor's opinion on them, and buyers read the report itself, including exceptions.
Two differences matter in practice:
- ISO 27001 is a pass or fail certificate against a management system standard, with a scoped statement. SOC 2 is a detailed report you choose to share under NDA.
- ISO 27001 requires a formal ISMS: a risk assessment, a Statement of Applicability listing which controls apply, internal audits and management review. SOC 2 focuses on the controls that meet the criteria you select.
How do you decide which one to pursue first?
Ask these questions:
- What do the customers in your pipeline name? Procurement checklists tell you. European enterprises and public bodies frequently name ISO 27001. US mid-market and enterprise buyers usually name SOC 2.
- Where will most revenue come from in the next twelve months? Pick the framework that unblocks that market.
- Do you need it for a specific deal? Ask whether the buyer will accept your existing SOC 2 report (and a bridge letter if the report period ended a while ago) or requires an ISO 27001 certificate by name.
- What's your team's capacity? ISO 27001 asks for management review, internal audit and a documented risk method, which suits companies ready to run a management system.
Don't decide from marketing pages. Ask two prospects in the target region what they accept. If both are open, choose the one your existing controls are closest to.
Where do the two overlap?
Much of the underlying work is the same, so effort on one carries over:
- Access control, including single sign-on, multi-factor authentication and reviews.
- Change management and secure development.
- Risk assessment and treatment.
- Incident response and business continuity.
- Vendor management.
- Security awareness training and policy acknowledgment.
- Logging, monitoring and vulnerability management.
The differences are mostly in structure and evidence. ISO 27001 expects an ISMS scope, leadership commitment, objectives, internal audits and a Statement of Applicability. SOC 2 expects a system description, and a Type 2 report also tests evidence sampled across a period. A compliance automation tool such as Vanta or Drata can help you keep one evidence set for both audits. In a demo, confirm which frameworks it covers and whether ISO 27001 is included for your scope.
What about GDPR and European customers?
Neither framework is a GDPR certification, and neither replaces GDPR duties. GDPR requires appropriate technical and organizational measures, data processing agreements and lawful transfer mechanisms for personal data leaving the EU, which are legal questions. Ask a privacy attorney how they apply to you.
What the frameworks do is give European buyers evidence that your security program is real. Expect their questionnaires to ask about data location, subprocessors, encryption, breach notification and deletion regardless of which report you hold. Keep your security questionnaire answers accurate and consistent so they don't have to be rewritten for each buyer.
How should you sequence them if you need both?
A workable path for a first-time program:
- Build the shared foundation: policies, access controls, change management, vendor reviews and training.
- Get the first framework your pipeline demands. If SOC 2, start with the readiness checklist and consider Type 1 vs Type 2.
- Extend to the second by adding what it needs: for ISO 27001, the ISMS documents, internal audit and management review; for SOC 2, the system description, plus the observation window if you're going for Type 2.
- Keep one evidence repository so both audits draw on the same records.
Plan the calendar with the auditors, since each firm has its own scheduling, and see how long SOC 2 takes for the phases. Don't promise buyers either credential until an auditor confirms your dates.
What Good Looks Like
You know which framework each target market requires, and one shared set of controls and evidence supports every audit you pursue.
Building The Capability (5-Stage Skill Ladder)
How to Get Started
Disclosure: We may earn a commission if you buy through some links on this page. It doesn't change what we recommend.
Frequently Asked Questions
Is ISO 27001 harder than SOC 2?
They're difficult in different ways. ISO 27001 requires a formal management system with internal audits and management review, which adds process. A SOC 2 Type 2 report requires evidence that controls operated over a period, while a Type 1 looks at design at a point in time. Effort depends on your maturity and scope more than on the framework.
Do European customers accept SOC 2?
Some do, particularly technology buyers, but many European enterprises and public bodies ask for ISO 27001 by name. Check your prospects' procurement requirements. A SOC 2 report can still support a review, but it may not satisfy a certificate requirement.
Can I get both ISO 27001 and SOC 2?
Yes, and many companies do. The controls overlap heavily, so you can reuse policies, evidence and processes. Plan the sequence around customer demand, and use one evidence repository so each audit draws on the same records.
Does ISO 27001 make us GDPR compliant?
No. It demonstrates a security management system but doesn't cover every GDPR obligation, such as lawful basis, data subject rights or transfer mechanisms. Work with a privacy attorney on GDPR duties and use ISO 27001 as supporting security evidence.
About the numbers
This guide doesn't quote a sourced benchmark. Figures in it are estimates or general guidance, so check them against your own numbers.
Related Guides
How to Answer Security Questionnaires Faster With an Answer Library
Build a reusable security questionnaire response library: answer format, evidence links, owners and review rules so sales reviews close in days, not weeks.
SOC 2 Readiness Checklist: 12 Things to Fix Before the Audit
A practical SOC 2 readiness checklist for startups: scope, policies, access, change control, vulnerability handling, vendors and evidence, in order.
SOC 2 Type 1 or Type 2 First? How to Decide
Should a startup start with SOC 2 Type 1 or go straight to Type 2? Compare what each proves, when buyers accept each, and how to sequence the audits.
SOC 2 Timeline: Each Phase and What Slows It Down
SOC 2 timelines depend on scope, gaps and report type. See the phases from scoping to the final report, what slows each one and how to plan a schedule.
What SOC 2 Auditors Expect From Security Awareness Training
What security awareness training satisfies a SOC 2 audit: content, timing, who must complete it and the evidence to keep for the auditor.
What Drives Penetration Test Cost for a Small SaaS Company
Understand what drives penetration test pricing for a small SaaS product, how to scope a test, compare quotes and get more value from the report.