Global GHG Standards: ISO and GHG Protocol Join Forces for Unified Climate Accounting
On 9 September 2025 ISO and the Greenhouse Gas Protocol announced a landmark strategic partnership to harmonize and combine their GHG portfolios into a co‑branded, unified global suite of standards for greenhouse‑gas emissions accounting and reporting.
The agreement aims to align methodologies, terminologies and reporting requirements to improve comparability and reduce duplication for corporates, auditors, regulators and voluntary market participants, while NGOs like Carbon Market Watch urge that harmonisation must raise the quality bar.
Key Takeaways
- Announcement : ISO and GHG Protocol agreed a strategic partnership to deliver unified global standards.
- Major outcome: the two bodies will harmonize existing portfolios and combine leading GHG standards into a co‑branded suite for GHG emissions accounting and reporting.
- Scope: joint harmonisation of accounting methodologies, terminology and reporting requirements across organizational and corporate scopes to reduce fragmentation.
- Why it matters: a single global baseline aims to improve comparability and consistency, reduce reporting burden and duplicated guidance, and shape corporate disclosure practices.
- Civil‑society reaction: Carbon Market Watch and other NGOs call for the process to “raise the quality bar,” stressing oversight, transparency and methodological rigor.
- Next steps to watch: publication of draft harmonized standards, public consultation periods, implementation guidance and transition provisions (detailed timeline not yet published).
- Immediate actions for practitioners: map existing inventories to the incoming framework, identify gaps, brief stakeholders, and prepare to engage in consultations and adopt transition guidance.
ISO and GHG Protocol partnership: unified global GHG accounting standards
We outline the landmark partnership and reported in the GHG Protocol blog, where ISO and the Greenhouse Gas Protocol agreed to harmonize and combine their GHG portfolios into a co‑branded, unified global standards suite. This alignment will standardize greenhouse gas accounting and reporting practices and make compliance simpler across jurisdictions. We recommend teams map existing inventories to the incoming framework, flag gaps, and engage early with standards guidance. For practical support, see our SBS Net-Zero Program.
What this means for practitioners
The combined standards will align definitions, scope boundaries, and methodological choices across documents. That reduces duplicated effort for multinational reporting and helps standardize emission-factor use. Practitioners should expect clearer cross-references between ISO procedures and GHG Protocol methods, which will simplify assurance and audit workflows. We recommend a structured gap analysis against your current inventory and an update to data collection protocols. If you want help translating the new text into operational controls, our advisory team can support.
Immediate actions and resources
Start by mapping your current inventories to the announced framework and flagging data, scope, and methodological gaps. Brief internal stakeholders finance, procurement, operations, and sustainability so they can align data sources and responsibilities. Update internal controls and ERP mappings to reflect new reporting lines. We provide practical tools and workshops that speed this work and reduce risk; view our resources. For teams planning assurance, engage assurance providers early and pilot mapped datasets before formal adoption.