Sustainability Assurance

Sustainability assurance is the independent verification of an organisation’s sustainability and climate disclosures, giving readers confidence that the information is reliable. In Australia, it is conducted under ASSA 5000, the standard for sustainability assurance engagements, much as a financial audit provides assurance over financial statements.

For entities caught by the mandatory climate disclosure regime, yes. The Corporations Act requires the auditor of an entity’s financial report to also assure its mandatory climate information, with the level of assurance phasing in from limited to reasonable over time.

Limited assurance is review-level, where the assurer concludes that nothing has come to their attention to suggest the information is materially misstated. Reasonable assurance is audit-level, providing a positive opinion to a higher level of confidence. The mandatory regime phases from limited assurance toward reasonable assurance.

Reasonable assurance phases in by reporting group and financial year, reaching reasonable assurance over all mandatory climate disclosures for years commencing 1 July 2030. Entities can choose to obtain reasonable assurance earlier.

Yes. The Australian sustainability assurance standard is framework-neutral, so it can be applied to voluntary sustainability and ESG disclosures. Many entities below the mandatory thresholds seek voluntary assurance to build credibility with investors, lenders, and supply-chain partners.

Under the Corporations Act, an entity’s financial report auditor, a registered company auditor, provides the assurance over its mandatory climate disclosures. Assurance is independent of the preparation of the report, which is why the readiness work and the assurance engagement are kept separate.