Carbon accounting standards and frameworks: GHG Protocol, ISO 14064, ESRS and VSME

Several standards govern how companies measure and report greenhouse gases. They overlap more than their names suggest: most rest on the same scope structure from the GHG Protocol and differ mainly in who must use them and what has to be disclosed.

The short version

GHG Protocol: the common language

The GHG Protocol Corporate Standard defines the three scopes and the rule that "Companies shall separately account for and report on scopes 1 and 2 at a minimum." It also sets the consolidation approaches (equity share, financial control, operational control) that decide which subsidiaries and joint ventures are in your inventory. See Scope 1, 2 and 3 emissions explained.

Two companion documents add detail:

• Scope 2 Guidance (2015) introduced dual reporting with location-based and market-based methods. A revision went to public consultation in October 2025, with final publication "expected in 2027". See location-based vs market-based Scope 2.
• Scope 3 Standard (2011) defines the 15 categories and requires companies to "account for all scope 3 emissions and disclose and justify any exclusions". See the 15 Scope 3 categories.

ISO 14064-1 and ISO 14067

ISO 14064-1:2018, "Greenhouse gases — Part 1: Specification with guidance at the organization level for quantification and reporting of greenhouse gas emissions and removals", covers the same ground as the GHG Protocol Corporate Standard but is written as a specification that can be verified against. It groups indirect emissions differently from the GHG Protocol's scopes, so inventories prepared under both usually include a mapping table. ISO lists it as current, last confirmed in 2024, with a revision (ISO/WD 14064-1.2) under development.

ISO 14067:2018 covers the carbon footprint of a single product rather than a company. It specifies "principles, requirements and guidelines for the quantification and reporting of the carbon footprint" of products, consistent with the life cycle assessment standards ISO 14040 and ISO 14044.

Using either standard does not by itself mean an inventory has been checked; verification is a separate step by an independent body.

ESRS and the CSRD

The Corporate Sustainability Reporting Directive (CSRD) requires in-scope EU companies to report under the European Sustainability Reporting Standards (ESRS); climate change, including greenhouse gas emissions, is covered by ESRS E1. Both have changed recently. According to the European Commission:

• In February 2025 the Commission proposed the Omnibus simplification package, which would "apply the CSRD only to the largest companies (those with more than 1000 employees)".
• On 9 December 2025 the European Parliament and the Council reached political agreement on the Omnibus I package.
• On 3 July 2026 the Commission adopted delegated acts amending the first set of ESRS (Delegated Regulation (EU) 2023/2772).

Because thresholds and timelines have moved several times, check the current text on the Commission's page before deciding whether your company is in scope. Companies that fall outside it are still often asked for emissions data by customers and lenders who are in scope.

VSME: the voluntary standard for SMEs

EFRAG delivered the Voluntary Sustainability Reporting Standard for non-listed SMEs (VSME) on 17 December 2024, and the European Commission adopted it as a Recommendation on 30 July 2025. It is meant for non-listed companies with fewer than 250 employees and has two parts: a Basic Module and a Comprehensive Module. Energy and emissions are covered in disclosure B3, "Energy and greenhouse gas emissions".

The aim is to give small companies one standard answer to the data requests they receive from banks and large customers. EFRAG has asked banks, investors and business counterparts to use VSME data points in their questionnaires "to avoid uncoordinated data requests".

Which should you follow?

• Most companies: measure with the GHG Protocol; it is what ESRS, VSME, CDP-style questionnaires and target-setting bodies expect your numbers to be based on.
• If a customer or regulator asks for ISO 14064-1 or verification: prepare the inventory so it can be mapped to ISO categories and verified.
• SMEs answering supply-chain questionnaires: VSME B3 is a sensible structure for presenting Scope 1 and 2 data.
• Setting a reduction target: see science-based targets explained.

LCALens is designed to align with the GHG Protocol and ISO 14064-1 methods but is not certified by any standards body, and using it does not replace independent verification.