Introduction

On July 29, 2026, the Greenhouse Gas Protocol (GHGP) and the International Organization for Standardization (ISO) announced they will merge their corporate carbon accounting standards into a single, co-branded global standard. The announcement also included the results of a public consultation on the Scope 2 Guidance and preliminary feedback on a new Actions and Market Instruments (AMI) standard. None of these changes are finalized yet, but they set the direction and timeline for how every company using GHG Protocol will measure and report emissions in the years ahead.

Key Takeaway

• GHGP and ISO will combine GHGP’s Scope 1, Scope 2, Scope 3, and Actions and Market Instruments (AMI) standards with ISO’s 14064-1 standard into one corporate standard, with an integrated public consultation planned for Q2 2027.
• The Scope 2 public consultation drew nearly 1,100 responses from 56 countries, centered on how companies should account for renewable energy purchases.
• A new multi-statement reporting approach is proposed under the AMI standard, separating physical emissions, market-based emissions, and a GHG impact statement into three distinct components.
• No new methodology has been finalized. Companies should continue reporting under the current Corporate Standard, Scope 2 Guidance (2015), and Scope 3 Standard until a revised or consolidated standard is adopted.
• The consolidation is a named milestone under the COP30 Action Agenda for harmonizing global greenhouse gas accounting standards.

What Did GHG Protocol and ISO Announce on July 29, 2026?

GHGP used the announcement to combine three separate updates into one release: the ISO consolidation plan, the outcome of the Scope 2 public consultation, and preliminary feedback on the AMI standard. The announcement frames all three as connected steps toward a single, more interoperable global accounting framework rather than three unrelated initiatives.

The World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD) jointly develop GHG Protocol standards, which are used by thousands of organizations worldwide and underpin many climate disclosure and target-setting programs. This makes any change to GHGP standards relevant to essentially every company that maintains a Scope 1, 2, or 3 inventory, regardless of which specific disclosure regulation it reports under.

GHGP CEO Tim Mohin said the changes would allow companies to “spend more time reducing emissions” once reporting is simplified and made more consistent across markets and jurisdictions.

GHGP-ISO Standard Consolidation: Scope 1, Scope 2, Scope 3, AMI, and ISO 14064-1

The consolidation brings together GHGP’s Scope 1, Scope 2, Scope 3, and AMI standards with ISO’s 14064-1 standard into one corporate standard. The two organizations describe the goal as reducing fragmentation and duplication between the world’s two most widely used carbon accounting frameworks, so that a company reporting under both today would eventually reconcile its inventory against a single reference document instead of two.

This work builds on a strategic partnership GHGP and ISO established the previous year and is identified as a milestone under the COP30 Action Agenda for harmonizing global greenhouse gas accounting standards. GHGP and ISO’s governance bodies have approved a timeline that includes an integrated public consultation on the future consolidated corporate standard in Q2 2027, with publication of the consolidated standard targeted for Q4 2028. Until that process concludes, the current Corporate Standard, Scope 2 Guidance, and Scope 3 Standard remain the applicable reference documents.

For multinational reporters that currently maintain parallel documentation to satisfy both GHGP-based disclosure frameworks and ISO 14064-1 certification requirements, a single co-branded standard would remove a persistent source of reconciliation work. GHGP has confirmed the new standard is expected to be published in a two-part structure, with additional guidance documents provided to assist users with implementation.

What Changed in the Scope 2 Guidance Public Consultation?

The Scope 2 public consultation closed after gathering nearly 1,100 responses from 56 countries, a scale of engagement GHGP characterizes as reflecting a wide range of views on how companies should account for renewable energy purchases in their GHG inventories. GHGP reports that feedback showed broad support for improving the accuracy, comparability, and integrity of electricity emissions accounting, even where respondents disagreed on the specific mechanism to achieve it.

In response to this feedback, GHGP is exploring multiple reporting approaches rather than committing to a single revised methodology. Any resulting proposal will still need to pass through the standard development process, including review by the Technical Working Group and approval by the Independent Standards Board, before it becomes part of an adopted standard.

This is the area most likely to affect day-to-day reporting practice for companies that rely on Power Purchase Agreements (PPAs) or unbundled renewable energy certificates (RECs) to support market-based Scope 2 claims, since the original 2015 Scope 2 Guidance is the document under active revision.

Actions and Market Instruments (AMI) Standard: The Multi-Statement Reporting Proposal

The AMI standard introduces a multi-statement reporting approach built around three distinct components. The first captures physical emissions from a company’s own operations and value chain. The second captures market-based emissions tied to instruments such as commodity certificates and mitigation-related contractual agreements. The third is a GHG impact statement that reflects the emissions effect of a company’s actions and investment decisions, calculated using consequential methods rather than attributional accounting.

GHGP reports that public feedback on this structure showed strong support, on the basis that separating these three components gives stakeholders a more complete picture of a company’s climate performance than a single blended emissions figure. Mohin described the intent as helping organizations present a more credible account of both the emissions they generate and the actions they take to reduce them.

The AMI workstream is being developed in coordination with the Scope 2 revision, since both address how contractual and market-based claims about emissions reductions should be represented in a GHG inventory.

How Does This Compare to the Current GHG Protocol Standards Companies Use Today?

This comparison shows that nothing in a company’s current Scope 1-3 inventory needs to change today. The practical shift is that the reference documents a sustainability team is building toward are now known to be moving targets, with the Scope 2 methodology and market instrument reporting structure the two areas most likely to require methodology updates once a revised standard is adopted.

What Will Companies Need to Do Once the Consolidated Standard Takes Effect?

Once the AMI multi-statement approach is adopted, companies will need a data structure capable of tracking physical emissions, market-based emissions, and consequential GHG impacts as three separate figures rather than one blended number. This means renewable energy contracts, RECs, and PPAs will need to be tagged and tracked as distinct line items rather than folded directly into a single Scope 2 total.

If the Scope 2 revision changes how market-based claims qualify for reporting, companies that rely on unbundled certificates will likely need more granular supplier and contract-level data than the current 2015 Guidance requires. Building this data infrastructure now, while the standard is still in consultation, reduces the risk of a disruptive scramble once a final methodology is published.

Companies do not need to change any current disclosure today. The practical preparation is architectural: ensuring that emissions data systems can be reconfigured to a multi-statement or revised Scope 2 structure without a full rebuild, once GHGP and ISO finalize the consolidated standard.

Conclusion

The July 2026 announcement does not change what any company needs to report this year, but it signals that the reference standards underlying every Scope 1-3 inventory are entering their most significant revision cycle since the original Scope 2 Guidance was published in 2015. Sustainability and finance executives who begin reviewing their Scope 2 market-based claims and market instrument tracking now will be better positioned when the consolidated standard reaches public consultation in Q2 2027.

ASUENE recommends that CSOs and sustainability leaders use this transition window to audit how their organization currently documents RECs, PPAs, and other market instruments, and to evaluate whether existing carbon accounting infrastructure can adapt to a multi-statement reporting structure without a full data rebuild. Executives ready to assess their Scope 2 and Scope 3 reporting readiness against these upcoming changes can begin that review with ASUENE’s carbon accounting platform.