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SOC 2 vs ISO 27001: which one does your startup need?

Updated 2026-09-06 · 7 min read · by Deepak Gandhi, who builds SOC2Starter

Both prove to a customer that you take security seriously. They are built differently, cost differently, and are recognised in different places. Picking the wrong one first is an expensive detour, and the deciding factor is usually geography plus who is asking.

The difference in one table

The structural difference that matters

SOC 2 audits controls. You describe what you do, the auditor tests whether it works, and the report says so at length. There is no pass mark — there is an opinion, and any exceptions are printed in the report for your customers to read.

ISO 27001 certifies a management system. It cares less about any individual control and more about whether you have a functioning machine for identifying risks, deciding what to do, and reviewing it: risk assessments, a Statement of Applicability, internal audits, management review. You either meet the standard and get certified, or you do not.

Put crudely: SOC 2 asks "is MFA on?"; ISO 27001 asks "how did you decide MFA was needed, and who checks that decision is still right?"

Which should you do first?

Start with SOC 2 if

• Your customers are American. This is the whole decision for most B2B SaaS.
• Deals are blocked right now and you need the fastest credible answer.
• You are small and want something proportionate to a ten-person company.

Start with ISO 27001 if

• Your customers are European, British, Asian or Middle Eastern, where the certificate is the recognised currency.
• You sell into regulated industries or government procurement that names it.
• You want a security programme you can point at internally, not just a report.

If you genuinely sell into both markets, most companies do SOC 2 first because it is faster to a usable artefact, then add ISO 27001 within a year or two.

How much of the work is shared?

A great deal — commonly estimated at half to three quarters of the underlying controls. Access control, MFA, onboarding and offboarding, change management, vendor management, encryption, backups, incident response, training: all of it counts twice.

What does not carry over is the ISO-specific machinery. If you did SOC 2 first, ISO 27001 will still ask you to build:

• A formal risk assessment methodology, not just a risk register.
• A Statement of Applicability justifying every Annex A control you included or excluded.
• An internal audit programme — you audit yourself before the certification body does.
• Documented management review at a set cadence.

So the second framework is meaningfully cheaper than the first, but it is not free.

Can one audit cover both?

Some firms offer combined SOC 2 and ISO 27001 engagements and share fieldwork where the evidence overlaps. It saves real money if you know you want both. It is not worth scoping a dual engagement speculatively — the saving is smaller than the cost of doing a framework nobody asked you for.

What customers actually do with each

A SOC 2 report is confidential and usually shared under NDA, because it contains a detailed description of your systems and any exceptions found. Enterprise security teams read it properly.

An ISO 27001 certificate is public and verifiable against the certification body's register. It is easier to hand out and carries less detail — which is an advantage at the top of a sales cycle and a disadvantage when a security team wants specifics.

The honest summary

Neither makes you secure. Both are commercial instruments that let a buyer's procurement process approve you. Do the one your buyers ask for, do it properly, and do not buy the second until somebody has actually asked for it.

Questions people ask

What is the difference between SOC 2 and ISO 27001?

SOC 2 is an attestation report issued by a licensed CPA firm that tests your controls against the AICPA Trust Services Criteria. ISO 27001 is a certificate issued by an accredited certification body that confirms you operate an information security management system meeting the ISO standard. SOC 2 is dominant in North America; ISO 27001 is the recognised currency in Europe, the UK, Asia and the Middle East.

Should a startup do SOC 2 or ISO 27001 first?

Follow your customers. If they are American, do SOC 2 first because it is what their procurement teams ask for and it produces a usable artefact faster. If they are European, British, Asian or Middle Eastern, or you sell into regulated or government procurement, start with ISO 27001.

Does SOC 2 count towards ISO 27001?

Much of the underlying control work carries over, commonly half to three quarters: access control, MFA, onboarding and offboarding, change management, vendor management, encryption, backups, incident response and training. What does not carry over is the ISO-specific machinery, namely a formal risk assessment methodology, a Statement of Applicability, an internal audit programme and documented management review.

Is ISO 27001 harder than SOC 2?

It is more prescriptive. SOC 2 lets you define controls that meet the criteria; ISO 27001 requires a management system with defined artefacts and asks you to justify every Annex A control you exclude. Many teams find SOC 2 faster to a first result and ISO 27001 more useful as an internal security programme.

Can you get SOC 2 and ISO 27001 at the same time?

Yes. Some audit firms run combined engagements and share fieldwork where evidence overlaps, which saves money if you already know you need both. It is not worth scoping speculatively, because the saving is smaller than the cost of certifying against a framework no customer asked for.