KPMG: A properly selected information security standard serves as a quality mark for partners

ISO 27001 and ISAE 3000 are two information security standards that consistently come to the forefront when organizations consider how to protect their data and systems—and how to demonstrate that protection to third parties.

ISO 27001 is an international standard that defines the requirements for an information security management system (ISMS). Through certification, a company demonstrates that it has documented processes, a risk assessment methodology, and control mechanisms in place to protect its information assets. The certification is widely recognized, broadly accepted, and sends a strong signal in market communication.

The strength of this standard lies in its scope: it covers the entire lifecycle of information security management, from establishing policies to employee training and physical security. ISO 27001 is an excellent starting point for organizations that want to build a structured information security framework and continuously develop it.

While ISO 27001 ensures that systems and processes are in place, ISAE 3000 provides independent assurance that the system actually works in practice. ISAE 3000 is a standard applied to non-financial information, including the evaluation of information security controls. Unlike ISO 27001 certification, ISAE 3000 does not merely confirm the existence of a system—it includes a thorough independent auditor’s assessment of whether controls were effective over a specific period. The result is a detailed and reliable report intended primarily for user organizations.

This is where ISAE 3000 clearly differs from ISO 27001. While the latter verifies whether a system complies with standard requirements, ISAE 3000 evaluates whether specific controls actually function effectively in practice—not just at a single point in time, but over a defined period, typically one year.

From a risk management perspective, ISAE 3000 is the most convincing for third parties

In today’s business environment, large volumes of sensitive data are often processed outside an organization’s own infrastructure—on cloud platforms, IT service providers’ systems, accounting services, or other shared environments. In such cases, organizations need not only to know that a partner holds a certificate, but also to understand how controls actually operate and what the risks are in the context of their own data processing.

An ISAE 3000 report is designed precisely to meet this need. It describes the service provider’s specific controls, assesses their effectiveness, and defines the user organization’s additional responsibilities—so-called complementary controls. This gives organizations a clear understanding of what they can rely on and what they must manage themselves.

In addition, an ISAE 3000 report is time-oriented: it typically covers a period of 6–12 months, allowing assessment of whether security controls have been consistently effective—not just at the moment of an audit. This is a crucial distinction for organizations whose risk management requires real, ongoing assurance.

From a regulatory and compliance perspective, ISAE 3000 also complements the requirements of the NIS2 Directive, which obliges organizations to assess and manage supply chain security risks. In this context, ISAE 3000-based assurance is one of the strongest forms of evidence that third-party risks are being actively managed.

ISO 27001 and ISAE 3000 are not alternatives—they complement each other. ISO 27001 establishes a strong foundation for internal information security management and provides globally recognized credibility. ISAE 3000 adds the depth and transparency required by modern supply chain and third-party risk management. When the question is who processes your data and whether their controls truly work, ISAE 3000 offers a more precise, detailed, and business-relevant answer.

Comparison of standards

• ISO 27001
  Demonstrates that an information security management system complies with standard requirements. Provides market recognition and is well-suited for building an internal framework. Focuses on processes and confirming the existence of documentation.
• ISAE 3000
  Recommended for third parties
  Provides an independent, detailed assessment of how controls actually operate over time. The report is designed with user organizations in mind and is ideal for evaluating the security of third parties.