SOC 2 Type II vs ISO 27001: Which Do You Need?

Introduction

I’ve had a client recently reach out to me debating whether to pusue an ISO 27001 or SOC 2 Type II certification and which was better for their company. I explained that unlike ISO, SOC 2 is an attestation report, not a certification and went on to provide more information about the differences between the two and helping them decide which was best suited for their needs.

Many organizations grapple with whether to pursue SOC 2 Type II or ISO 27001 first, often because a client, sales opportunity, or security questionnaire suddenly raises the question. While the two frameworks are often mentioned together, they serve different purposes and meet different customer expectations. Understanding these distinctions is the key to choosing the one that best supports your business growth.

For the purpose of this comparison, I’m referring specifically to SOC 2 Type II, since Type I is a point‑in‑time assessment and aligns more closely with ISO 27001’s certification model.

1. Different Origins, Objectives, and Customer Expectations

ISO/IEC 27001 is an international standard used widely across Europe and other global markets. It focuses on establishing and maintaining an Information Security Management System (ISMS) and demonstrating that security risks are managed in a structured, repeatable way.

SOC 2, on the other hand, is an attestation framework developed by the AICPA (American Institute of Certified Public Accountants) in the United States, designed to allow independent auditors to report on whether a service organization’s controls meet defined Trust Service Criteria and operate effectively over a defined period. Because SOC 2 is deeply embedded in US procurement processes, especially for SaaS and cloud-based services, it has become the defualt expectation for many American enterprise customers.

2. Certification vs. Attestation

ISO 27001 results in a certification issued by an accredited certification body. It confirms that a company has implemented an ISMS that meets the standard’s requirements at the time of the audit, and the outcome is binary – certified or not certified.

SOC 2 produces an attestation report issued by a CPA firm. It does not certify an organization. Instead, it provides assurance to customers and stakeholders through a detailed auditor’s report on whether controls were suitably designed and operated effectively during the audit period.

SOC 2 vs ISO 27001 Comparison

Category	SOC 2 Type II	ISO 27001
Type	Attestation report	Accredited certification
Origin	AICPA (U.S.)	ISO (International)
Market Expectation	Default expectation for US enterprise and SaaS procurement	Widely required across Europe & international markets
Audit Focus	Design + operation effectiveness of controls over a defined period	ISMS structure, governance & risk management practices
Coverage Period	3-12 month testing window	Point in time
Outcome	Idependent auditor’s opinion and detailed report	Formal certification valid for 3 years, with annual surveillance audits
Primary Audience	Customers wanting evidence of operational controls	Customers expecting structured security program

3. How This Shows Up in Real Life

This difference becomes obvious during sales and onboarding.

A company selling into Europe may be asked for ISO 27001 certification as a baseline requirement. The certificate is often sufficient to progress commercial discussions.

That same company selling into the U.S. is frequently asked for a SOC 2 Type II report instead. An ISO certificate alone is usually not enough, not because ISO 27001 is weaker, but because American enterprise customers expect period-based evidence showing how controls operated over time. Depending on the criticality of the system and underlying data, even European customers may request a SOC 2 Type II for the additional information and context it provides.

The frameworks answer different customer questions, in different markets.

4. Control Design vs. Control Operation

ISO 27001 places strong emphasis on defining policies, procedures, and risk management processes.

SOC 2 goes a step further and requires evidence that controls operated consistently in practice.

For example, ISO 27001 may only require you define a process for removing user access witin 24 hours of termination. Under SOC 2, auditors will test actual termination events and verify when access was removed. If access lingered beyond the stated timeframe, the control fails, even if the policy itself is perfectly documented.

5. So Which Do You Need?

Rather than focusing on which standard is “better,” the more practical question is: Which requirement stands between you and a closed deal?

If security questionnaires, RFPs, or prospect conversations repeatedly ask for one of them, that’s your answer.

Some companies begin with SOC 2 because their U.S. customers want a detailed, period‑based report. Others need ISO 27001 because it’s the recognized baseline in international markets or required by partners abroad. Both paths are valid, and many organizations eventually pursue both as they grow.

Wherever you start, the good news is that the underlying security themes overlap. With thoughtful planning, work done for one framework can accelerate readiness for the other, reducing effort and helping you mature your security program in a structured way.

In my client’s case, they required SOC 2 but were considering ISO in the future. I recommended mapping SOC 2 controls to ISO requirements during the SOC 2 audit to streamline future ISO preparation.

Not sure whether you need ISO 27001 or SOC 2? Contact us for a free consultation!