SOC 2 vs. ISO 27001: Which security standard is right for you?

SOC 2 vs. ISO 27001: Which Security Standard Is Right for You?

SOC 2 and ISO 27001 are among the most commonly chosen compliance standards. Nevertheless, many organizations ask themselves which of the two they actually need. Is one better than the other? The answer depends on various factors and on what you are trying to achieve.

Read on to understand the differences and similarities between the two frameworks – and to learn which one to choose in which situation.

What is SOC 2?

SOC 2 (System and Organization Controls) reports are independent assurance reports that document how a company designs and operates key security and compliance controls. These reports are based on the auditing standards of the American Institute of Certified Public Accountants (AICPA) and the applicable Trust Services Criteria (TSC).

The main purpose of SOC 2 reports is to evaluate all information systems of an organization that are relevant for security, availability, processing integrity, confidentiality and privacy. Many organizations regularly undergo SOC 2 audits performed by independent CPA firms to demonstrate compliance with these criteria.

During these audits, the auditor assesses whether the controls are:

• appropriately designed,

• implemented at the time of the report and

• operating effectively over the reporting period.

SOC 2 reports are therefore important assurance reports performed in line with AICPA standards, in particular AT-C 105 and 205 under SSAE 18.

What is ISO 27001?

ISO 27001 is an internationally recognized standard that defines the requirements for establishing, implementing, maintaining and continually improving an Information Security Management System (ISMS).

It helps organizations:

• protect confidential information,

• ensure data integrity and

• maintain the availability of information.

ISO 27001 focuses on systematic risk management: identifying threats and vulnerabilities and implementing appropriate risk treatment measures. The standard is flexible and can be tailored to organizations of different sizes, industries and maturity levels.

What is the difference between SOC 2 and ISO 27001?

The main difference is:

• SOC 2 evaluates the effectiveness of your controls that protect sensitive information.

• ISO 27001 evaluates the effectiveness and maturity of your management system (ISMS) as a whole.

Both aim to strengthen information security but do so from different angles.

1. Scope and focus

The scope of SOC 2 can be limited to a single Trust Services Criterion, with security being mandatory. The applicability of the other criteria (availability, processing integrity, confidentiality, privacy) depends on the services you provide. This makes SOC 2 a flexible framework that typically includes between 70 and 150 controls, depending on the selected categories.

ISO 27001, by contrast, looks at all aspects of information security. Organizations must establish, maintain and continuously improve an ISMS and address the relevant requirements of the standard as well as the 93 controls in Annex A.

2. Attestation vs. certification

A SOC 2 audit is carried out by a licensed CPA firm and results in a SOC 2 report. There is no formal “SOC 2 certification”. The attestation process requires you to:

• select the relevant Trust Services Criteria,

• design and implement controls,

• provide evidence for testing.

An ISO 27001 audit is conducted by an accredited certification body that evaluates the effectiveness of your ISMS. If the audit is successful, the organization receives an ISO 27001 certificate.

3. Target markets

SOC 2 is particularly popular in North America and widely accepted by US companies. It is especially relevant for:

• cloud providers,

• SaaS companies,

• IT service providers and managed services.

Customers – especially in the US – often explicitly expect a SOC 2 report as part of their vendor due diligence.

ISO 27001 is globally recognized and accepted by organizations worldwide as evidence of a robust ISMS, especially in:

• IT and SaaS,

• financial services,

• telecoms,

• healthcare.

Even if customers do not explicitly require ISO 27001, certification significantly increases credibility and can help you win new business.

4. Framework structure and audit process

SOC 2 is structured around the five Trust Services Criteria, each containing a number of detailed requirements. Organizations are audited against the principles they select, with the security criterion being mandatory.

A SOC 2 audit results in either:

• a SOC 2 Type I report – assessing the design of controls at a point in time, or

• a SOC 2 Type II report – assessing both design and operating effectiveness over a period of typically 6–12 months.

ISO 27001 is structured into clauses and Annex A controls. The controls are grouped into four themes: organization, people, technology and physical security. The latest version includes 93 controls and the ISMS is audited against the Plan–Do–Check–Act (PDCA) cycle.

The certification process has two main external audit stages:

• Stage 1: review of documentation and ISMS design,

• Stage 2: in-depth assessment of implementation and effectiveness.

After certification, annual surveillance audits are required.

5. Timeframes

Typical implementation and audit timelines:

• SOC 2: around 6–12 months to obtain the first report.

• ISO 27001: around 6–24 months depending on scope and complexity.

SOC 2 reports are usually valid for one year and need to be renewed annually. ISO 27001 certificates are valid for three years, with annual surveillance audits.

6. Level of detail in reporting

SOC 2 reports are highly detailed and include:

• auditor’s opinion,

• management assertion,

• system description,

• list of controls, tests and results.

ISO 27001 audit reports tend to be less granular and focus more on summary findings and any nonconformities, rather than describing every control in detail.

Similarities between ISO 27001 and SOC 2

Despite their differences, ISO 27001 and SOC 2 share several important similarities:

1. Voluntary but widely recognized

Both are voluntary standards, not legal requirements. However, both are internationally recognized and widely requested as proof of a strong security posture.

2. Overlap of controls

ISO 27001 and SOC 2 have an estimated 90 % overlap in controls, including:

• incident and business continuity management,

• access control,

• physical security,

• change management,

• vendor management,

• backup and recovery.

3. Focus on information security

Both frameworks aim to protect information from unauthorized access and disclosure. SOC 2 focuses more on customer data and service provider controls, while ISO 27001 focuses on the ISMS.

4. Third-party validation

Both require external audits:

• SOC 2 → attestation report,

• ISO 27001 → certification.

5. Ongoing maintenance and improvement

Neither framework is a one-time effort. Both require:

• continuous monitoring,

• regular reassessment and

• ongoing improvement of controls and processes.

Which framework should you use – ISO 27001 or SOC 2?

The choice depends on:

• where your customers are (US vs. global),

• what your customers explicitly require,

• your growth strategy and risk appetite.

The two frameworks are not mutually exclusive. In practice, many growing organizations implement both SOC 2 and ISO 27001. Due to the high overlap, controls can be mapped and reused, which significantly reduces the additional effort.

From an audit perspective, this overlap can make the compliance process much more efficient. Many organizations start with one framework and add the other as they expand into new regions and customer segments.

FAQs

Is an ISO 27001 certification equivalent to a SOC 2 report? No. ISO 27001 certification demonstrates robust information security management but does not replace a SOC 2 report. Especially US customers will often still expect SOC 2.

How can organizations benefit from having both SOC 2 and ISO 27001? Showcase your status:

• on your website (badges, logos),

• on social media,

• via a public Trust Center or security page.

This builds customer trust and can shorten sales cycles.

What is the cost difference between SOC 2 and ISO 27001? ISO 27001 tends to be more expensive because implementation is broader in scope. Security-only SOC 2 audits may start around USD 20,000, while ISO 27001 certification audits can range roughly between USD 30,000 and 60,000 depending on scope and size.

Can you “fail” a SOC 2 audit? You do not formally pass or fail, but the auditor may issue:

• a qualified opinion,

• an adverse (negative) opinion, or

• a disclaimer of opinion if evidence is insufficient.

What happens if you fail an ISO 27001 certification audit? The auditor issues a nonconformity report highlighting major and minor nonconformities. Corrective actions and possibly a follow-up audit are required. Existing certificates can be suspended, and surveillance frequency can increase.