Which should you get first: SOC 2 or ISO 27001?
Get SOC 2 first if your revenue pipeline is dominated by US and Canadian B2B buyers. Get ISO 27001 first if you sell mainly into the EU, UK, or other markets that follow international standards. The underlying control work overlaps heavily, practitioners commonly estimate 60-80%, so whichever framework you build first funds most of the second.
This is a sales decision disguised as a security decision. Both frameworks force the same operational hygiene: access reviews, change management, incident response, vendor due diligence, centralized logging. What differs is the artifact your buyer's procurement team recognizes and the machinery around it. Map where your next twelve months of revenue actually comes from, the deal that stalls in procurement is the deal that decides. Then design the control set so the second framework becomes an increment, not a restart.
- ▸Mostly US pipeline: SOC 2 Type II, with a Type I as an early milestone
- ▸Mostly EU, UK, or MENA pipeline: ISO 27001
- ▸Genuinely split: build one mapped control set, certify in the order your deals demand
What is the actual difference between SOC 2 and ISO 27001?
SOC 2 is an attestation report issued by a licensed CPA firm against the AICPA Trust Services Criteria. ISO 27001 is a certification of your information security management system (ISMS), issued by an accredited certification body against an international standard. One produces a detailed confidential report your customers read; the other, a public certificate plus a Statement of Applicability.
The structural differences matter in practice:
- ▸SOC 2 Type I evaluates control design at a point in time; Type II tests operating effectiveness over an observation window, typically 3-12 months. Buyers who know what they are asking for want Type II.
- ▸Trust Services Criteria: Security is mandatory; Availability, Confidentiality, Processing Integrity, and Privacy are optional. Most SaaS companies attest Security plus Availability and Confidentiality.
- ▸ISO 27001:2022 combines management clauses 4-10 (risk assessment, leadership, internal audit, improvement) with 93 Annex A controls. New certificates now sit on the 2022 revision, the transition window from the 2013 edition has closed; confirm dates with your certification body.
- ▸Accreditation matters. An ISO certificate from a body not accredited by UKAS, DAkkS, ANAB, or a national equivalent will be challenged in enterprise procurement. Ask any prospective certifier who accredits them.
Which certification do your buyers actually expect?
In practice, US and Canadian enterprise procurement asks for a SOC 2 Type II report almost by default, while EU and UK buyers ask for ISO 27001, increasingly because their own NIS2 and DORA supplier obligations map onto it. If you sell into both markets you will eventually hold both; the only real question is sequencing.
A few less obvious dynamics:
- ▸A SOC 2 report is shared under NDA and answers a security questionnaire in depth. An ISO certificate is public but thin, so sophisticated buyers ask for the Statement of Applicability alongside it.
- ▸Regulated EU buyers push their compliance downstream. A bank scoping DORA or an essential entity under NIS2 will vet you as a supplier either way, holding ISO 27001 shortcuts that assessment. The control mapping in The NIS2 Engineering Checklist: 40 Controls Mapped to Evidence shows how much of that work overlaps with certification.
- ▸Neither framework is GDPR compliance, though a mapped Annex A helps evidence the Article 32 security measures, see GDPR Compliance for SaaS Startups: A Practical 2026 Guide.
How much does each cost, and how long does it take?
For a 20-100 person software company, first-year SOC 2 Type II typically lands between 30,000 and 80,000 EUR all-in; a first ISO 27001 certificate typically between 25,000 and 70,000 EUR. Expect three to six months of preparation, then a 3-12 month SOC 2 observation window or an ISO stage 1 plus stage 2 audit.
Where the money actually goes:
- ▸Audit fees. SOC 2 Type II engagements from reputable CPA firms typically run 15,000-40,000 EUR. ISO certification bodies typically charge 8,000-20,000 EUR for the initial stage 1 and stage 2 audits, with annual surveillance audits on top.
- ▸Compliance automation platforms (Vanta, Drata, Secureframe, and similar) typically cost 10,000-30,000 EUR per year depending on headcount and frameworks. Useful, not sufficient.
- ▸A penetration test is a de facto expectation for both, even where the standard does not strictly mandate one. Budget it separately.
- ▸Engineering time is the biggest unbudgeted line. Remediation, evidence wiring, and auditor interviews typically consume 0.25-0.5 FTE across two quarters.
One sequencing trick: a SOC 2 Type I is achievable within weeks once controls exist, and it holds a US enterprise deal open while the Type II observation window runs. All ranges vary with scope, region, and auditor brand, treat them as planning numbers, not quotes.
How much of the work overlaps between the two?
Most of it. Access control, change management, incident response, logging, vendor management, HR security, business continuity, and risk assessment all map between the Trust Services Criteria and ISO 27001 Annex A. Practitioner mappings commonly put the overlap at 60-80% of the operational effort. What does not transfer is structural rather than technical.
- ▸ISO uniquely requires the ISMS machinery: a maintained risk register with treatment plans, a Statement of Applicability covering all 93 Annex A controls, internal audits, management reviews with minutes, and demonstrated continual improvement.
- ▸SOC 2 uniquely requires a written system description and months of period-of-time evidence the auditor samples: tickets, access review records, change approvals.
The way to make the overlap real is a single common control framework: define each control once, map it to both standards, and generate evidence from pipelines rather than screenshots. That is exactly the approach described in ISO 27001 Evidence as Code: Building an ISMS Engineers Don't Hate, and it applies to SOC 2 unchanged, because the auditor's samples come from the same systems.
When does it make sense to do both at once?
Pursue both simultaneously only if your pipeline is genuinely split across markets, or a live enterprise deal demands the one you lack. Otherwise sequence them: once a mapped control set and automated evidence collection exist, the second framework typically adds 30-50% of the first one's effort rather than another 100%.
If you do run both:
- ▸Pick auditors deliberately. Some firms deliver both the SOC 2 attestation and the ISO certification audit, or partner to do so, and will reuse walkthroughs and samples.
- ▸Align the calendars. Aim the ISO surveillance audit and the SOC 2 observation window at a single annual audit season instead of two.
- ▸Budget for audit fatigue. Every audit pulls the same senior engineers; two uncoordinated audits can quietly consume a quarter of a small platform team's year.
Which mistakes make a first certification slow and expensive?
Four repeat offenders: scoping the entire company instead of the production platform; assuming the compliance platform is the program; writing policies nobody operates; and starting the SOC 2 observation window before controls actually run, which voids months of evidence. Each typically costs one to three months of delay and real money.
- ▸Scope narrowly. Certify the product platform and the teams that touch it. You can widen scope at renewal.
- ▸Operate before you attest. Auditors sample reality. A quarterly access review that has run twice beats a beautiful policy that has run never.
- ▸Treat the audit as verification, not discovery. A readiness gap assessment four to six months out is far cheaper than audit findings.
If a customer audit arrives before any certification can, How to Pass a Security Audit for Your First Enterprise Client covers the shorter path. And if you also carry GDPR, NIS2, or DORA obligations, fold them into the same control set from day one, The 2026 SME Cybersecurity Checklist for GDPR, NIS2 and DORA is the mapping to start from.
How TuniCyberLabs helps
We build the control set once and map it everywhere it needs to land: SOC 2, ISO 27001, NIS2, DORA, and customer questionnaires. That means a scoped gap assessment, remediation engineering (SSO, centralized logging, access reviews, backup restores that actually run), evidence-as-code wired into your CI, and auditor selection with support through stage 2 or the Type II window. If a certification decision is blocking a deal, talk to us, we will tell you honestly which one to chase first.