Following their partnership announcement in 2025, the Greenhouse Gas Protocol (GHG Protocol) and the International Organization for Standardization (ISO) have now confirmed that they will combine their corporate carbon accounting standards into a single, co-branded global standard.
The proposed standard will bring together the GHG Protocol’s existing Scope 1, 2 and 3 standards, alongside its work on Actions and Market Instruments (AMI), with ISO 14064-1.
Why the standards are being aligned
Using different carbon accounting standards can create duplication for businesses, particularly where emissions data needs to meet different reporting or assurance requirements.
GHG Protocol is already widely used for corporate emissions reporting, including within wider sustainability reporting frameworks. ISO 14064-1 sets out principles and requirements for quantifying and reporting organisation-level greenhouse gas emissions and is widely used as a basis for verification.
Bringing them together is intended to create a single foundation for corporate GHG accounting, making it easier for businesses and other users to work from a common methodology.
The consolidation is also a key milestone in the COP30 Action Agenda, with GHG Protocol and ISO working to advance the harmonisation of global greenhouse gas accounting standards.
It will not, however, automatically change existing regulatory or reporting requirements. Organisations such as the International Sustainability Standards Board (ISSB) and European Commission will need to decide separately whether and how this standard is incorporated into their respective requirements.
What could change under the new standard
The proposed framework could also change how some emissions are measured and reported.
Development work is already looking at areas including organisational boundaries, Scope 2 accounting and Scope 3 reporting. Potential changes include stronger requirements around renewable energy procurement and contractual instruments, greater disclosure of Scope 3 categories subject to thresholds, and changes to the treatment of Scope 3 Category 15 emissions for financial institutions.
The integration of the AMI workstream could be particularly significant. The proposed approach would enable companies to report three distinct components: emissions from their own operations and value chains (physical emissions); emissions tied to market instruments such as commodity certificates and mitigation-related contractual agreements (market-based emissions); and the emissions impact of their actions and investment decisions using consequential methods (a GHG impact statement).
GHG Protocol says preliminary feedback indicates strong support for this approach, which is intended to provide a more complete and transparent picture of corporate climate actions, market instruments and emissions outcomes.
Scope 2 remains a moving target
GHG Protocol has also published feedback from its consultation on proposed changes to Scope 2 accounting.
The consultation received nearly 1,100 responses from 56 countries and considered how renewable energy procurement should be reflected in corporate emissions reporting, including proposals around hourly matching and deliverability.
The feedback showed significant differences in stakeholder views. There was limited support for the hourly matching proposal in its current form, while many respondents highlighted practical challenges and the need for a phased approach.
GHG Protocol is now exploring multiple reporting approaches in response to the feedback, so businesses should not treat the consultation outcome as the final approach to Scope 2 accounting. Any further proposals will go through the organisation’s standard development process, including review by its Technical Working Group and Independent Standards Board.
For now, focus on fundamentals
The proposed consolidated standard is still some way from becoming a finished framework. An integrated public consultation on the future corporate standard is planned for Q2 2027, with the final standard expected by Q4 2028.
With the final standard still some way off, businesses can use this time to strengthen the foundations of their emissions reporting. Reliable emissions data and a clear accounting approach will remain important as the standards develop.
If you’re reviewing your existing emissions data or starting to understand your organisation’s carbon footprint, the team at Sustainable Energy First are on hand to help build a robust approach to emissions measurement and reporting.
