What the EU’s new sustainability assurance standard means for businesses

On 12 November 2026, the European Commission opened a targeted consultation on the future EU standard for limited assurance of sustainability reporting. The standard will set out how statutory auditors and independent assurance providers reach their conclusions on CSRD reporting.

What’s changing?

• A common EU standard: The Commission will adopt limited assurance standards through a delegated act. These build on technical advice from the Committee of European Auditing Oversight Bodies (CEAOB), which uses ISSA 5000 as its basis and adapts it to EU law.
• A single assurance conclusion for the sustainability statement: Assurance providers will conclude on three things:
  • fair presentation under the ESRS, including the double materiality assessment process
  • the Article 8 EU Taxonomy disclosures
  • the digital mark-up, once digital tagging requirements apply

What’s the timeline?

The consultation is open until 18 January 2027, and the Commission must adopt the delegated act by 1 July 2027. The CEAOB proposes that the standard apply to reporting periods beginning on or after 15 December 2027, with earlier application permitted. The consultation asks stakeholders whether mandatory application should start in 2027, 2028 or later, so the application date is not yet confirmed.

What does this mean for businesses?

A common standard will make assurance more predictable and its expectations more explicit. Companies should expect assurance providers to examine how reported information was produced as closely as the information itself.

The double materiality process falls within the scope of the conclusion. That places the documentation of methods, thresholds and judgements under scrutiny. Taxonomy KPIs will be tested against the screening criteria and reconciled to the financial statements. Coordination between sustainability and finance teams will therefore carry as much weight as the disclosures.

Some groups may require third-party assurance under both the EU standard and another framework. For them, the EU standard will apply in full, which may affect how existing assurance engagements are scoped.

How can Nexio Projects help?

Nexio Projects supports companies across their full CSRD and sustainability reporting journeys. This runs from double materiality assessments, gap analyses and operational implementation all the way through to drafting the sustainability statement, EU Taxonomy reporting and assurance readiness.

The final standard is still being developed, but organisations should start strengthening their audit trail now, ahead of their next reporting cycle.

Contact our reporting experts to discuss what this means for your organisation.

Sources: 

European Commission (2026) Targeted consultation on limited assurance standard. Available at: https://finance.ec.europa.eu/regulation-and-supervision/consultations-0/targeted-consultation-limited-assurance-standard_en (Accessed: 13 November 2026). ⁠

Segal, M. (2026) ‘EU Commission releases draft sustainability reporting assurance standards’, ESG Today, 12 November. Available at: https://www.esgtoday.com/eu-commission-releases-draft-sustainability-reporting-assurance-standards/ (Accessed: 13 November 2026). ⁠