In November 2024, the International Auditing and Assurance Standards Board (IAASB) issued International Standard on Sustainability Assurance (ISSA) 5000, General Requirements for Sustainability Assurance Engagements, and in January 2025, the International Ethics Standards Board for Accountants (IESBA) issued International Ethics Standards for Sustainability Assurance (Including International Independence Standards) and Other Revisions to the Code Relating to Sustainability Assurance and Reporting.
ISSA 5000 is the first of a new suite of standards on sustainability assurance and will serve as a comprehensive, stand-alone standard suitable for any assurance engagement on sustainability information, regardless of how that information is presented. ISSA 5000 addresses both reasonable and limited assurance engagements and may be used for sustainability information prepared under any sustainability reporting framework or under multiple frameworks. The standard is also profession agnostic, meaning sustainability assurance practitioners who are not professional accountants may also use the standard.
International Ethics Standards for Sustainability Assurance (Including International Independence Standards) (IESSA) is a new part, Part 5, of the International Code of Ethics for Professional Accountants (Including International Independence Standards), and sets ethics standards for all sustainability assurance engagements and independence standards for sustainability assurance engagements reported in accordance with a general-purpose framework required by law or regulation or publicly disclosed. IESSA is also profession agnostic.
ISSA 5000 is effective for assurance engagements on sustainability information reported for periods beginning on or after December 15, 2026, or as at a specific date on or after December 15, 2026. The IAASB clarified in the basis for conclusions that if the sustainability information subject to assurance includes sustainability information for both a period and an “as at” date, the effective date would be for periods beginning on or after December 15, 2026.
IESSA is generally effective for assurance engagements on sustainability information reported for periods beginning on or after December 15, 2026, or as at a specific date on or after December 15, 2026. Revisions to Parts 1 to 3 of the International Code of Ethics for Professional Accountants (Including International Independence Standards) is effective as of December 15, 2026. Provisions applicable to assurance work on sustainability information performed at value chain components are effective for periods beginning on or after December 15, 2026, or as at a specific date on or after December 15, 2026.
