SOC 2 vs ISO 27001: Which Do You Need?

SOC 2 and ISO/IEC 27001 are two security assurance frameworks SaaS companies are frequently asked about in security questionnaires and procurement reviews. Both give customers independent evidence that a vendor manages information security risk, and both cover much of the same ground: access control, change management, incident response, vendor oversight and risk assessment. They differ in who issues them, what the deliverable looks like, how long it lasts and which buyers expect it.

This guide explains those differences, where the two frameworks overlap, and how SaaS teams typically decide which to pursue first or whether to run both. Figures on cost and timing are attributed to the audit and certification firms that published them, since actual numbers vary with company size and scope.

Attestation vs certification

The core distinction is the type of assurance each produces. SOC 2 is an attestation: an independent auditor examines a service organization's controls and issues an opinion in a report. ISO/IEC 27001 is a certification: an auditor assesses whether the organization's information security management system (ISMS) conforms to the requirements of an international standard, and if it does, a certificate is issued.

The issuers differ as well. SOC 2 was developed by the American Institute of Certified Public Accountants (AICPA), and SOC 2 examinations are performed by licensed CPA firms, as audit firms A-LIGN and Cherry Bekaert both note. ISO/IEC 27001 is published jointly by ISO and the International Electrotechnical Commission (IEC), but ISO states on its own standard page that it does not certify organizations. Certificates are issued by independent certification bodies, which are in turn accredited by national accreditation bodies such as UKAS in the United Kingdom.

The deliverables look different. A SOC 2 report is a lengthy document containing management's assertion, the auditor's opinion, a system description and, for Type 2, the tests performed and their results. Schellman notes that SOC 2 reports are designed to be shared with customers, typically under a nondisclosure agreement, while an ISO/IEC 27001 certificate is a one- to two-page document and the underlying audit report is generally for internal use.

How ISO/IEC 27001:2022 is structured

ISO/IEC 27001:2022, published in October 2022 according to ISO, has two main parts. Clauses 4 through 10 contain the mandatory management system requirements: context of the organization, leadership, planning, support, operation, performance evaluation and improvement. These cover defining the ISMS scope, top management involvement, risk assessment and treatment, resources and awareness, internal audits, management review and corrective action. An organization cannot exclude any of these clauses.

Annex A is a reference list of 93 controls grouped into four themes. Certification body Glocert lists 37 organizational controls, 8 people controls, 14 physical controls and 34 technological controls. The 2013 edition had 114 controls in 14 domains, and the 2022 revision added 11 new controls, including threat intelligence, information security for cloud services, configuration management, data leakage prevention, monitoring activities and secure coding. Organizations record which Annex A controls apply, and justify any exclusions, in a Statement of Applicability.

The transition from the 2013 edition has ended. Under the International Accreditation Forum's transition rules (IAF MD 26), summarized by RSM Certification, certified organizations had until October 31, 2025 to move to the 2022 version if their certificate was to be maintained, and LRQA published similar guidance ahead of that deadline. New certifications and recertifications have been issued against the 2022 edition since late 2023. ISO also published an amendment in 2024 adding climate action considerations to the management system clauses.

How SOC 2 is structured

SOC 2 examinations evaluate controls against the AICPA Trust Services Criteria, which are organized into five categories: security, availability, processing integrity, confidentiality and privacy. As audit firm Linford and Co. explains, security is the only required category. Its criteria, known as the common criteria and labeled CC1 through CC9, cover the control environment, communication, risk assessment, monitoring, control activities, logical and physical access, system operations, change management and risk mitigation. The other four categories are added when they are relevant to the services and to customer commitments.

There are two report types. A Type 1 report addresses whether controls are suitably designed and implemented as of a specific date. A Type 2 report also tests whether controls operated effectively over a review period, which A-LIGN describes as usually between three and 12 months. Many enterprise buyers ask for Type 2 because it shows controls working over time rather than on a single day.

Unlike ISO/IEC 27001, SOC 2 does not prescribe a fixed control list. The service organization designs its own controls to meet the criteria, and the auditor tests those controls. This gives teams flexibility in how they meet each criterion, but it also means two SOC 2 reports can contain quite different control sets.

Side-by-side comparison

Scope: ISO/IEC 27001 certifies a management system, and Cherry Bekaert describes it as covering the entire ISMS within the defined scope, including governance, documentation, assets and suppliers. SOC 2 focuses on the system that supports specific services, described in detail in the report.

Prescriptiveness: ISO/IEC 27001 has fixed clause requirements and a defined reference control set. SOC 2 has defined criteria but leaves control design to the organization.

Timing of assurance: A SOC 2 Type 2 report looks back over a completed review period. An ISO/IEC 27001 certificate states that the ISMS conformed at the time of audit and is maintained through ongoing surveillance.

Validity and cycle: ISO/IEC 27001 certificates are valid for three years. Certification body ISOQAR describes the cycle as an initial Stage 1 (documentation and readiness) and Stage 2 audit, surveillance audits at the end of years one and two, and a recertification audit before expiry. SOC 2 has no multi-year certificate; organizations typically repeat the examination every year.

Disclosure: An ISO/IEC 27001 certificate can be shared publicly, and certificates can be verified with the issuing body. A SOC 2 report is usually shared under NDA. Organizations that want a public summary can obtain a SOC 3 report, a general-use version without the detailed test results.

Geography and buyers: Cherry Bekaert describes SOC 2 as primarily preferred by customers in North America and ISO/IEC 27001 as more widely recognized internationally, especially in Europe. In practice, US enterprise buyers often request a SOC 2 report, while European and Asia-Pacific buyers and public sector organizations more often ask for an ISO/IEC 27001 certificate.

Where the frameworks overlap

Much of the operational work is shared. Schellman lists access control, change management, incident response, business continuity, risk management and security policies as common control areas. Cherry Bekaert estimates a 65 to 75 percent overlap between the requirements, a figure that depends on which Trust Services Criteria are in scope and how the ISMS is defined.

The AICPA publishes a mapping of the Trust Services Criteria to ISO/IEC 27001, available to members as a spreadsheet, which helps teams see where one set of controls can satisfy both. Typical areas that map cleanly include user provisioning and access reviews, encryption, logging and monitoring, vulnerability management, vendor risk management, security awareness training and incident handling.

The gaps are mostly on the ISO side. ISO/IEC 27001 requires management system elements that SOC 2 does not require in the same form: a documented ISMS scope, a formal risk assessment and treatment methodology, a Statement of Applicability, internal audits of the ISMS, management review and a nonconformity and corrective action process. Going the other way, SOC 2 requires a detailed system description and, for Type 2, evidence that each control operated throughout the review period, which calls for consistent evidence retention.

A practical way to measure overlap for a specific company is a gap assessment against whichever framework is not yet in place. Starting from an existing control inventory, the team maps each control to the relevant Trust Services Criteria and Annex A controls, marks items that satisfy both, and lists what is missing. The result shows which policies, procedures and evidence can be reused, which need adjusting to meet the other framework's wording or depth, and which management system processes must be built. This also helps estimate how much additional audit preparation the second framework will require.

Choosing which to pursue first

Cherry Bekaert advises that the starting point depends on the customer base, and Schellman recommends looking at the market, customer needs and any regulatory requirements. Several patterns are common among SaaS companies.

SOC 2 first tends to fit companies selling mainly to North American businesses, especially mid-market and enterprise buyers whose security questionnaires ask for a SOC 2 Type 2 report. A Type 1 can serve as an early deliverable while the Type 2 review period runs.

ISO/IEC 27001 first tends to fit companies whose customers are primarily in Europe or other international markets, companies selling into public sector or regulated buyers that reference ISO standards, and teams that want a formal management system in place before they scale.

Both at once can fit companies with a mixed customer base or active deals in several regions. It requires more upfront effort but allows one control set to be designed for both frameworks from the start.

On timing, Cherry Bekaert cites three to 12 months for SOC 2 and six to 12 months for initial ISO/IEC 27001 certification, and notes that ISO costs are typically higher because of certification and implementation requirements. A-LIGN cites a range of $20,000 to more than $150,000 for SOC 2, depending on company size, complexity and scope. These figures include readiness work, and any single company's costs may fall outside them.

Doing both efficiently

Organizations that pursue both frameworks can reduce duplicated work by building a single control library mapped to the Trust Services Criteria and to Annex A, rather than maintaining two separate programs. Schellman describes a unified control matrix, combined testing and coordinated evidence collection as ways to create efficiencies. A single compliance platform can hold that library for both frameworks: Scytale, for example, supports SOC 2 and ISO 27001 among more than 80 frameworks, so teams can run both programs in one place with the same dedicated GRC expert included in the subscription.

Aligning scope helps. If the ISMS scope and the SOC 2 system boundary cover the same products, infrastructure and teams, most evidence can serve both audits. Aligning the calendar also helps: some organizations schedule ISO surveillance audits close to the end of the SOC 2 review period so that auditors can use the same samples and interviews where their standards allow.

Using a single assessor that operates both a CPA practice and an accredited certification body is another option Schellman describes, though the two engagements still follow different standards and produce separate deliverables. Whatever the approach, the ISO-specific management system elements, particularly the risk assessment, Statement of Applicability, internal audit and management review, should be planned early, since they cannot be derived from SOC 2 testing alone.

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