ISO 27001 vs. NIS2: Two Sides of the Same Coin?

Understanding the overlap — and key differences — between ISO 27001 and NIS2 to build a resilient, compliant cybersecurity posture.

The rise of cyber threats and evolving regulatory landscapes have made information security a top priority for businesses across Europe. Two major frameworks stand out in this space: ISO/IEC 27001 and the NIS2 Directive. While they share common goals and principles, they are not interchangeable. Organizations must understand their similarities and differences to achieve compliance effectively.

How Similar Are ISO 27001 and NIS2?

ISO 27001 and NIS2 have a strong overlap, particularly in their focus on risk management, security controls, and incident response. However, they differ in scope, application, and regulatory enforcement.

A rough comparison suggests that:

If an organization is ISO 27001 certified, it has covered around 70-80% of NIS2 requirements.
Conversely, complying with NIS2 without ISO 27001 covers only about 50-60% of ISO 27001, as NIS2 does not require a full Information Security Management System (ISMS).

Key Similarities

Both frameworks emphasize:

Risk Management: Organizations must identify, assess, and mitigate cybersecurity risks.
Security Controls: Measures such as access control, encryption, and security monitoring are essential in both standards.
Incident Reporting: Both require timely detection, reporting, and response to security incidents.
Supply Chain Security: Organizations must ensure their third-party vendors adhere to cybersecurity best practices.
Continuous Improvement: Regular security assessments and audits are mandated.

Key Differences

Why ISO 27001 Alone is Not Enough for NIS2 Compliance

While ISO 27001 provides a strong foundation for NIS2, it does not fully address all regulatory obligations. NIS2 imposes additional requirements, such as:

Sector-Specific Compliance: Organizations in industries like energy, transport, banking, and healthcare must meet stricter NIS2 rules.
Government Oversight: National authorities will monitor and enforce NIS2 compliance, with potential fines for non-compliance.
Mandatory Incident Reporting: Companies must notify authorities within 24 hours of a significant cybersecurity incident.

How to Bridge the Gap?

Organizations already compliant with ISO 27001 can align with NIS2 by:

Reviewing NIS2-Specific Requirements: Conduct a gap analysis to identify missing areas.
Strengthening Incident Response: Ensure your incident handling procedures meet NIS2’s strict reporting deadlines.
Enhancing Supply Chain Security: Assess and manage risks related to third-party vendors.
Engaging with Regulators: Understand the expectations of national authorities enforcing NIS2.
Regular Compliance Assessments: Keep up with evolving regulations to maintain compliance.