ISO 27001 Compared to Other Information Security Standards: What’s the Difference?

ISO 27001 is often mentioned alongside ISO 27002, the NIST Cybersecurity Framework, Cyber Essentials and SOC 2, but each serves a different purpose.

This article explains how ISO/IEC 27001 differs from other information security standards, what makes it a certifiable Information Security Management System (ISMS), and how it fits alongside guidance frameworks, baseline schemes and assurance reports.

Comparing information security standards means looking at what each one is designed to do, who it is for and what kind of assurance it provides. Some, like ISO/IEC 27001, are certifiable management system standards. Others, such as ISO/IEC 27002 and the NIST Cybersecurity Framework, are guidance frameworks. Cyber Essentials is a UK assurance scheme, while SOC 2 is an attestation report used mainly in US-driven markets.

A useful comparison looks at type, scope, assurance level and implementation effort.

ISO 27001 is a certifiable management system standard, while ISO 27002 is a supporting guidance standard that explains information security controls in more detail. ISO 27001 sets the requirements for establishing, implementing, maintaining and continually improving an ISMS. ISO 27002 describes how individual controls can be interpreted and applied.

In practice, organisations that pursue ISO 27001 certification use ISO 27002 as a reference when choosing and designing controls. ISO 27001 includes Annex A, which lists control themes. ISO 27002 expands on these with guidance and examples. You can use ISO 27002 guidance without becoming certified, but certification is always against ISO 27001, not ISO 27002.

ISO 27001 is an international, certifiable management system standard, whereas the NIST Cybersecurity Framework is a voluntary guidance framework published by the US National Institute of Standards and Technology. ISO 27001 focuses on building an ISMS that manages risks across the organisation, while NIST CSF provides functions and categories to assess and improve cybersecurity posture.

Geographically, ISO 27001 is used worldwide, including in the UK, Europe and many global supply chains. NIST CSF originated in the United States, particularly for critical infrastructure, but is now used more widely as a reference model.

ISO 27001 is a comprehensive ISMS standard, while Cyber Essentials is a UK government-backed baseline scheme that focuses on a small set of technical controls. ISO 27001 covers governance, risk assessment, controls, monitoring and continual improvement across people, process and technology. Cyber Essentials concentrates on core topics such as secure configuration, access control and patch management.

For many UK organisations, Cyber Essentials or Cyber Essentials Plus is a starting point that demonstrates baseline cyber hygiene to customers or public sector buyers. ISO 27001 certification is a deeper step that requires an ISMS, risk-based control selection and ongoing internal audit.

ISO 27001 is an international management system standard with certification, while SOC 2 is an attestation report based on the AICPA’s Trust Services Criteria, widely used in US markets. ISO 27001 certification assesses whether an organisation’s ISMS meets the requirements of ISO/IEC 27001 for a defined scope. SOC 2 involves an independent auditor reporting on the design and, for Type 2, the operating effectiveness of controls over a period.

The choice is often driven by customer expectations and geography. Global or UK based organisations may prioritise ISO 27001 certification, especially where supply chains and tenders reference it. US based customers, particularly in SaaS and cloud services, may request SOC 2 reports instead. Some organisations align with both over time.

The right choice depends on your customers, markets and security maturity.

Key factors to consider include:

1. Customer and regulator expectations in your target markets
2. Whether you need formal certification, a framework for improvement, or both
3. Existing internal capabilities and the level of change your organisation can support

For many growing UK organisations, ISO 27001 certification offers a structured, internationally recognised ISMS, while frameworks such as NIST CSF and schemes such as Cyber Essentials support internal improvements and UK specific assurance.

Many organisations use a GRC platform to centralise their ISMS, controls and evidence, so these standards are easier to run in practice.