Scope 1, 2 and 3 emissions explained, with examples
What Scope 1, 2 and 3 greenhouse gas emissions mean, how each is calculated, where companies usually start, and how to get help with a first inventory.
Greenhouse gas emissions reporting groups a company’s emissions into three scopes, following the GHG Protocol, the most widely used accounting standard. The scopes tell you where emissions come from and who controls them.
Scope 1: direct emissions
Emissions from sources your company owns or controls. Examples: fuel burned in boilers and furnaces, fuel used in company vehicles, and leaks of refrigerant gases. You calculate them from activity data (litres of fuel, kilograms of refrigerant) multiplied by emission factors.
Scope 2: purchased energy
Emissions created when someone else generates the electricity, steam, heating or cooling that you buy. There are two ways to report electricity, and the GHG Protocol asks for both:
- Location-based: the average emissions of the local grid.
- Market-based: the emissions of the specific supply you chose, such as a renewable tariff or certificate.
Scope 3: everything else in the value chain
Indirect emissions upstream and downstream of your business. The GHG Protocol defines 15 categories, for example purchased goods and services, transport and distribution, business travel, employee commuting, use of sold products and end-of-life treatment. For many companies Scope 3 is the largest part of their footprint and the hardest to measure.
How the calculation works
Emissions = activity data × emission factor. Quality depends on both. Spend-based estimates are quick but rough. Supplier-specific data is more accurate but takes more effort. Most companies start with estimates and improve over time, which is acceptable if you say so openly.
Where to start
- Set your organisational boundary (control or equity share).
- Pick a base year.
- Collect Scope 1 and 2 data first.
- Screen all 15 Scope 3 categories, then calculate the ones that matter most.
- Keep evidence for every number.
What reporting rules require
CSRD’s ESRS E1 and the ISSB’s IFRS S2 both require Scope 1, 2 and (with conditions) 3 disclosures. See ESRS, ISSB and GRI compared.
Try it, then get help
Get a rough idea with the free carbon footprint estimator. Compare tools in carbon accounting software, or specialists in GHG inventory services.
IsoMetrix
Software suite combining ESG, risk and compliance, and health and safety modules for industrial and financial companies.
One Click LCA
LCA and EPD software for construction and manufacturing, covering buildings, infrastructure and product carbon footprints.
Normative
Carbon accounting platform for calculating, reporting and reducing Scope 1, 2 and 3 emissions, now merging with Greenly.
Benchmark Gensuite
EHS and ESG software suite with reporting tools including BRSR and BRSR Core.
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This guide is general information, not legal, tax or investment advice. Rules change; check the official sources and talk to an adviser before you rely on it.
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