Corporate carbon accounting is entering its most significant restructuring since the Corporate Standard was first published. On 29 July 2026, the Greenhouse Gas Protocol confirmed a new direction and a revised timeline that will reshape how organisations build, evidence and assure emissions inventories.
What is changing in the GHG Protocol, and when?
GHG Protocol and the International Organization for Standardization (ISO) will combine their corporate carbon accounting standards into a single, harmonised global corporate standard. The updated standard will consolidate the Corporate Standard (2004), Scope 2 Guidance (2015), Scope 3 Standard (2011), and the Actions and Market Instruments workstream, together with ISO's 14064-1. The revised timeline includes a consolidated public consultation in Q2 2027 and publication of the joint corporate standard in Q4 2028. The standard is expected to follow a two-part structure, supported by separate implementation guidance.
Why merge GHG Protocol and ISO standards?
The stated aim is to reduce fragmentation, increase interoperability and give organisations a single trusted foundation for climate reporting, cutting duplication and simplifying reporting for companies, investors and policymakers. Consolidation also enables a single coordinated public consultation process rather than parallel workstreams.
For UK organisations already reconciling SECR, IFRS S2 and customer-driven disclosure requests, a single reference framework should reduce methodology conflict over time.
What changes are proposed for Scope 3?
GHG Protocol released a March 2026 progress update setting out proposed Scope 3 revisions, focused on reporting completeness, value-chain boundaries and data-quality disclosure. It remains draft material, with a full public consultation draft still to come.
The proposals that matter most operationally:
- A 95% coverage floor. Companies would need to account for at least 95% of required Scope 3 emissions, with no more than 5% excluded, replacing the current "disclose and justify exclusions" wording.
- Disaggregation by data type. Emissions would be classified by source type rather than reported as a single category total. Proposed tiers distinguish primary or activity-based data from spend-based or EEIO estimates.
- Verification disclosure. Companies would state whether Scope 3 inventories are fully, partially, or not verified.
- Tighter allocation rules and a proposed new Category 16. Company-level emissions allocation would be restricted to single-industry suppliers.
What is happening with Scope 2 and renewable electricity claims?
The Scope 2 public consultation closed on 31 January 2026, drawing close to 1,100 responses from 56 countries and surfacing divergent views on renewable energy purchasing, alongside broad support for improving accuracy and comparability.GHG Protocol will now revise the consultation draft with its Independent Standards Board and Technical Working Group, exploring whether multiple reporting approaches reflecting different theories of change could address the range of views received.
Separately, the Actions and Market Instruments workstream is developing a multi-statement reporting structure that would separate physical inventory emissions, market-based emissions, and the impacts of climate actions, reported transparently and without netting between categories. A public consultation on that draft standard is planned for Q2 2027.
What should UK businesses do now?
Nothing in the revisions displaces current SECR obligations, and the existing standards remain in force until the consolidated edition is published. The practical risk is not compliance in 2026 it is data architecture.
Organisations reporting material Scope 3 should begin tagging activity data by type at the point of capture, prioritising primary supplier data in high-impact categories, and maintaining a documented methodology trail that can survive a boundary or allocation change without rebuilding the inventory. Spend-based proxies that currently sit unlabelled inside category totals will become visible.
How can iCOR support organisations with their carbon reporting obligations?
iCOR helps organisations to reduce reliance on spreadsheets, save time, and feel more confident about legal and operational risk and compliance. The platform includes a self-audit tool that maps applicable environmental, health, and safety legislation into a tailored legal register, and allows you to track compliance actions, assign responsibilities, and present your progress. iCOR tracks GHG Protocol developments as they happen alongside your statutory SECR duties, flagging what changes and when, from the consolidated public consultation in Q2 2027 through to publication of the joint GHG Protocol–ISO corporate standard in Q4 2028.
Book a demo here to learn how iCOR can help you with carbon reporting and disclosure, turning compliance into an integrated and continuous process that is accessible to everyone.