GHG Protocol
The globally dominant standard for measuring and reporting greenhouse gas emissions. Used by companies, regulators, and investors worldwide as the foundation for almost every climate disclosure regime in existence.
What it is
The Greenhouse Gas (GHG) Protocol is the world’s most widely used standard for measuring and reporting corporate greenhouse gas emissions. It’s developed jointly by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD), and has been the de facto global reference for emissions accounting since the early 2000s.
The cornerstone is the Corporate Accounting and Reporting Standard, which provides the methodology for preparing a corporate-level GHG inventory. It covers seven greenhouse gases — CO₂, CH₄, N₂O, HFCs, PFCs, SF₆, and NF₃ — and classifies emissions into three Scopes: Scope 1 (direct) emissions from sources you own or control — fuel combustion in your boilers, fugitive emissions from refrigerants, on-site processes, your own vehicle fleet. Scope 2 (indirect, energy) emissions from the generation of the electricity, steam, heat, and cooling you purchase from utilities. Scope 3 (other indirect) all other emissions across your value chain, both upstream and downstream. The Corporate Value Chain (Scope 3) Standard formalizes 15 categories: purchased goods and services, capital goods, fuel and energy-related activities, upstream and downstream transportation, waste, business travel, employee commuting, leased assets, processing and use of sold products, end-of-life treatment, franchises, and investments.
Beyond the Corporate Standard, the GHG Protocol suite includes the Scope 2 Guidance (covering location-based and market-based reporting), the Product Life Cycle Accounting and Reporting Standard (for product-level footprints), and a range of sector-specific calculation tools.
What makes GHG Protocol uniquely important is that it’s been adopted as the underlying measurement framework for almost every major climate disclosure regime: IFRS S2, EU ESRS E1, California SB 253, the UK SRS, Australian AASB S2, the Science Based Targets initiative (SBTi), and the CDP climate questionnaire all reference or require GHG Protocol methodologies. Even when a company reports through a different framework, the underlying emissions data is almost always prepared using GHG Protocol.
Who needs it
In most cases, if you’re calculating emissions at all, you’re using GHG Protocol — directly or through a framework that references it.
California’s SB 253 (Climate Corporate Data Accountability Act) requires companies with over USD 1 billion in annual revenues “doing business in California” to disclose Scope 1 and 2 emissions starting in 2026 (for fiscal year 2025) and Scope 3 emissions starting in 2027.
EU CSRD/ESRS requires in-scope companies to disclose Scope 1, 2, and (after phase-in) Scope 3 emissions. ESRS E1 references GHG Protocol principles for definitions and accounting.
IFRS S2 (ISSB) expects emissions to be measured in a manner consistent with GHG Protocol, including all three Scopes where material. ISSB-aligned regimes in Australia, the UK, Hong Kong, Singapore, and a growing list of other jurisdictions effectively require GHG Protocol-style accounting.
The Science Based Targets initiative (SBTi) explicitly requires companies to follow GHG Protocol Corporate Standard, Scope 2 Guidance, and Scope 3 Standard when setting and tracking science-based emissions targets. CDP structures its climate questionnaire around GHG Protocol categories and requires Scope 1, 2, and 3 disclosures using its methodology.
For a mid-sized company outside any of these specific mandates, the most common driver to use GHG Protocol is being in the value chain of a regulated company. Customers report Scope 3 emissions that include yours, lenders ask for GHG Protocol data, and investors expect emissions disclosure aligned with the standard. Even informal ESG questionnaires assume GHG Protocol-style accounting. In practical terms, if you’re tracking emissions, you’re using GHG Protocol.
How to start
If you’re new to GHG Protocol, start with Scopes 1 and 2. They’re the most direct and the easiest to calculate — you need fuel consumption data, refrigerant top-ups, vehicle mileage, and electricity bills.
Scope 3 is where most companies spend the most time: screen the 15 categories to identify which ones are material for your business, then calculate them using either spend-based or activity-based methods depending on data availability.
Common questions
Questions teams ask about GHG Protocol.
Also working with the other frameworks?
We’re early and building deliberately.
If you’re developing or investing in this space, we’d like to hear from you.