ISO 27001 vs SOC 2: Which Does Your Customer Require?

ISO/IEC 27001 is a certification: a certification body audits your information security management system against an international standard and issues a certificate. SOC 2 is a report: an independent CPA firm examines your description of a specific system and its controls against the AICPA's Trust Services Criteria and gives an opinion, and a Type 2 report includes the auditor's tests of those controls and the results. The right choice is whichever your customers' security teams accept, so ask them before you spend on either.

Our SOC 2 readiness services scope the report, close the gaps and organize the evidence before a CPA firm starts fieldwork; we do not issue reports or certificates. If you are choosing between report types, our guide to SOC 2 Type 1 vs Type 2, and SOC 1 vs SOC 2 covers that decision.

What is the difference between ISO 27001 and SOC 2?

They answer different questions. ISO/IEC 27001 asks whether you run a management system that identifies information security risks, treats them and keeps improving, across a scope you define. A SOC 2 is an attestation: the AICPA's SOC 2 guide describes it as an examination of a service organization's description of its system and of controls relevant to security, availability, processing integrity, confidentiality or privacy. One proves you manage security as a system; the other gives customers an auditor's view of specific controls.

Which does your customer require?

Ask in writing which report or certificate the customer's security or procurement team accepts, for which services and how recent it must be. The answer usually falls into one of these patterns:

• The questionnaire names SOC 2 or the Trust Services Criteria: plan for a SOC 2, and confirm whether a Type 1 is acceptable while a Type 2 period runs.
• A contract or tender names ISO/IEC 27001: plan for certification, and agree the scope with the customer before you agree it with the certification body.
• Customers in several countries: ask each one whether it accepts a SOC 2 at all. The ISO/IEC 27001 page on ISO's site cites more than 70,000 certificates across 150 countries in its 2022 survey.
• The request comes from a customer's finance team or auditor: they may need a SOC 1, which the AICPA describes as covering controls relevant to customers' internal control over financial reporting. Neither 27001 nor SOC 2 answers that question.
• The customer accepts either: choose the one more of your other customers ask for, because you will maintain it every year.

Do ISO 27001 and SOC 2 overlap?

At the control level, a great deal. The AICPA calls its Trust Services Criteria outcome-based and publishes mappings from the criteria to other frameworks, and ISO/IEC 27002 describes the 93 controls a 27001 program draws on; our ISO 27001 vs 27002 comparison explains how those two standards fit together. In practice the same configured controls, such as identity and access management, logging, backups, incident response and supplier reviews, produce evidence for both.

The differences sit around the controls. ISO/IEC 27001 adds the management system: a defined scope, a documented risk assessment and treatment, internal audits, management reviews and corrective action. SOC 2 adds a written system description and, in a Type 2, evidence that each control operated, sampled by the auditor. Adding the second usually takes less work than the first, because the controls are already running.

How does NIST compare with ISO 27001 and SOC 2?

NIST frameworks organize a program; they do not produce something you hand a customer as proof. NIST's Cybersecurity Framework FAQ says NIST does not offer certifications of CSF implementations and has no plans to develop a conformity assessment program, and the CSF is used voluntarily by most organizations. NIST SP 800-171 is different again: it applies when a federal contract involving controlled unclassified information requires it.

So the three-way comparison usually resolves like this: use the NIST CSF to structure your security program, then prove it to customers with a SOC 2 report or an ISO/IEC 27001 certificate, depending on which they accept.

Which fits a small team?

Usually the one your largest customer asks for first, kept to the smallest scope that customer accepts. Both need a named owner for every control and evidence that the controls run, so neither is a one-time project. The practical differences for a small team:

• SOC 2 can start with a Type 1 report on control design while the Type 2 period runs, which suits a company with a deal waiting on a report.
• ISO/IEC 27001 asks for management activity a small company may not have yet: a risk process, internal audits and management reviews on a schedule.
• Selling mostly to US companies whose questionnaires cite SOC 2 points to SOC 2 first. Tenders and customers that name 27001 point the other way.

If you later need both, the second one reuses most of the control work from the first.

What drives the cost and effort of each?

We publish no prices, and an audit fee depends on the firm and the scope. The budget for either has the same shape:

• Scope. The services, systems, sites and people covered. It is the biggest lever on every other line.
• Remediation. MFA, device management, logging, backups and recovery tests, whatever the gap assessment finds.
• Documentation. For 27001, the ISMS records, risk assessment and treatment, internal audit and management review. For SOC 2, the system description and evidence collected across the period.
• The independent party's fee. A certification body for 27001, a CPA firm for SOC 2, each quoted from your scope; for SOC 2 the report type, the criteria in scope and the length of the period also move the fee.
• Compliance software, if you want a platform to track evidence. It watches controls; it does not configure them.
• Staff time to own controls, answer auditor requests and repeat the cycle every year.

How does NetSys help with SOC 2 and ISO 27001?

We prepare you; the independent party judges. For SOC 2 we choose the Trust Services Criteria and systems to report on based on what customers ask for, draft the system description, run the gap assessment, implement the technical controls in Microsoft 365, Entra ID, Intune and your cloud platform, write policies your team will follow and keep an evidence calendar with named owners. When you are ready, we help you select an independent CPA firm and support fieldwork.

For ISO/IEC 27001 work, our cybersecurity consulting engagements assess your controls against the framework, rank the gaps and write the policies, and for managed clients we map the controls we already run to the framework you choose. Agreements run month to month, and you can start with our free remote external penetration test, limited to available information and an agreed external scope.

Book a call with a NetSys engineer and bring the security questionnaire or contract clause that started this. We will help you read what it actually requires before you commit to an audit.

Frequently asked questions

What is the difference between ISO 27001 and SOC 2?

ISO/IEC 27001 is a certification of your information security management system, issued by a certification body against an international standard. SOC 2 is a CPA firm's report on a specific system and its controls, measured against the AICPA's Trust Services Criteria. The first proves you manage security as a system; the second gives customers an auditor's opinion and, in a Type 2, test results.

Is SOC 2 or ISO 27001 better?

Neither is better in general. The better one is the one your customers accept: if their questionnaires name SOC 2, that is your answer, and if their contracts or tenders name ISO/IEC 27001, they expect the certificate.

Which fits a small team?

The one your largest customer requires, at the smallest scope that customer accepts. SOC 2 can begin with a Type 1 report; ISO/IEC 27001 requires a running management system with internal audits and management reviews.

What affects the cost, implementation and support?

Scope, remediation, documentation, the auditor's fee and staff time. Support continues after the first audit, because both are repeated: a SOC 2 report ages, and a certificate depends on the management system continuing to run.

Is SOC 2 compliance the same as ISO 27001 certification?

No. SOC 2 compliance usually means a company holds a current SOC 2 report from a CPA firm, which is an attestation with an opinion rather than a certificate. ISO/IEC 27001 certification means a certification body has audited the ISMS and issued a certificate for a stated scope.

Can one audit cover SOC 2 and ISO 27001?

No single engagement produces both, because a CPA firm issues the SOC 2 report and a certification body issues the ISO certificate. You can run one set of controls and present the evidence to both, which is where most of the savings come from.