Assurance over Greenhouse Gas Emissions Disclosures

Background: Assurance requirements included in the legislation

The Financial Sector (Climate-related Disclosures and Other Matters) Amendment Act 2021 (the Act) has the following key assurance implications:

  • Mandatory assurance over greenhouse gas (GHG) emissions disclosures. The mandatory assurance regime comes into effect on the third anniversary of the Act obtaining Royal Ascent, i.e., October 2024.
  • The assurance engagement must comply with applicable auditing and assurance standards issued by the External Reporting Board (XRB).
  • Includes a criminal offence for non-compliance with applicable auditing and assurance standards.

Proposals relating to the reporting of GHG emissions

The Climate-related Disclosures Final Consultation document also clarifies the scope of the assurance engagement, so we are interested in hearing views on this. 

The minimum level of assurance for GHG emissions proposed is set at Limited Assurance, however this will be revisited once the assurance regime has commenced (from 27 October 2024).


Update on our development of a mandatory assurance regime

We have conducted analysis of four existing assurance standards for the purposes of this regime. These include:

  • ISAE (NZ) 3410 Assurance Engagements on Greenhouse Gas Statements
  • ISAE (NZ) 3000 (Revised) Assurance Engagements Other than Audit or Reviews of Historical Financial Information
  • PES 1 International Code of Ethics for Assurance Practitioners (including International Independence Standards) (New Zealand)
  • PES 3 Quality Management for Firms that Perform Audits or Reviews of Financial Statements, or Other Assurance or Related Services Engagements

It is important that the standards we develop are accessible to all practitioners including non-accountant assurance practitioners, who may not be familiar with XRB standards.

To that end, we are focused on developing assurance standards that are:

  • fit for purpose
  • do not create unnecessary barriers to entry
  • are freely available and useable
  • delivered as a single set of standards for the regime.

The project will be undertaken in three streams, with a focus on:

  • specific requirements for the assurance over GHG disclosures
  • quality management requirements for the regime
  • ethical requirements for the regime.

We have established an advisory panel of experienced assurance practitioners to advice the XRB as we undertake our analysis. The panel included the following members: 

Marje Russ (NZAuASB member), Becky Lloyd (Toitū), Karen Tipper (Toitū), Brett Tomkins (Deloitte), Pip Best (EY).

In December 2022, we issued a consultation document and an exposure draft, which can be found here.

We are interested to hear from you if you have views for us to consider.



Voluntary assurance over other aspects of the climate statement

While the Act establishes a narrow scope for the mandatory assurance engagement, we understand that some entities may voluntarily seek assurance over other parts of the climate statement.

ISAE (NZ) 3000 (Revised) is the existing XRB assurance standard that applies to voluntary assurance engagements over other parts of or the climate statement. In 2021, we published the IAASB’s comprehensive guidance to support application ISAE 3000 (Revised) to Extended External Reporting (EER) Assurance Engagements along with a navigation tool to help point users to relevant chapters and illustrative examples.

We are interested to hear your views in relation to the application of existing assurance standards and guidance for voluntary assurance engagements over other aspects of the climate statement.