The International Organisation for Standardisation (ISO) and the Greenhouse Gas Protocol (GHG Protocol) have announced a landmark strategic partnership to harmonise their existing greenhouse gas (GHG) standards and co-develop a new, co-branded international standard for GHG emissions accounting and reporting.
In this alert, we explain what has happened and what this might mean for your business.
What’s happened?
On 9 September 2025, ISO and the GHG Protocol announced a new partnership to harmonise their existing GHG standards, including standards from the ISO 1406X family of standards, alongside the GHG Protocol Corporate Accounting and Reporting, Scope 2 and Scope 3 Standards.
Under the agreement, ISO and the GHG Protocol will also work on a joint product carbon footprint standard to support companies seeking more granular data from across their value chains.
The agreement reflects recent calls for harmonisation by the B7 - an engagement community which represents the interests of the business community across G7 countries. It is expected to reduce complexity and provide greater consistency for stakeholders, including companies, their shareholders and regulators
Both ISO and GHG Protocol standards have been widely adopted by organisations around the world.
The ISO sets standards for a broad range of management systems, including environmental management and GHG accounting.
The GHG Protocol was developed by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD), and sets standards for measuring, managing and reporting greenhouse gas emissions.
The ISO and GHG Protocol standards were developed separately and have areas of overlap. This has created duplication across the two standards, while also providing varying guidance on emissions scopes and verification.
What does this mean for you?
The GHG Protocol Corporate Accounting and Reporting Standard is the prescribed standard for measuring greenhouse gas emissions under Australia’s mandatory sustainability reporting regime, unless the reporting entity is required by a jurisdictional authority or exchange to use a different measurement method.
Therefore, any changes resulting from this strategic partnership may have implications for companies that are required to prepare sustainability reports under the Corporations Act.
The ISO1406X family of standards may also be used under a number of Australian reporting regimes, including under the Climate Active program, the Clean Energy Regulator’s Corporate Emissions Reduction Transparency reporting initiative, as well as international reporting regimes.
Companies that are using the ISO1406X family of standards should also monitor the outcomes of the partnership.
What should you do now?
Companies should monitor this development to understand whether any changes will be required to their sustainability reporting.
For further information or assistance on navigating sustainability reporting, please contact a member of the King & Wood Mallesons or Owl Advisory team.

