The 15 Scope 3 categories explained simply
Scope 3 emissions are value-chain emissions. The GHG (greenhouse gas) Protocol divides them into 15 categories so companies can structure what would otherwise become an unmanageable list of suppliers, travel, logistics...
Scope 3 emissions are value-chain emissions. The GHG (greenhouse gas) Protocol divides them into 15 categories so companies can structure what would otherwise become an unmanageable list of suppliers, travel, logistics, products and investments.
Quick answer: the 15 Scope 3 categories cover upstream and downstream emissions outside a company's direct operations and purchased energy. Not every category is relevant for every business, but every company should screen them before deciding what to calculate in detail.
For related Scope 3 work, read our guides to Scope 3, Scope 3 for SMEs, supplier questionnaires and supplier data collection.
How this article differs from the basic Scope 1, 2 and 3 guide
The basic explainer defines the scopes. This article is about sorting the 15 Scope 3 categories into a practical work plan. The useful question is not "can we calculate everything immediately?" It is "which categories are relevant, material and decision-useful enough to prioritise first?"
The 15 categories
| # | Category | Plain-English meaning |
|---|---|---|
| 1 | Purchased goods and services | Emissions from things the company buys. |
| 2 | Capital goods | Emissions from long-life assets such as machinery, buildings or IT. |
| 3 | Fuel and energy-related activities | Upstream emissions linked to fuels and energy not already counted in Scope 1 or 2. |
| 4 | Upstream transportation and distribution | Freight and distribution before products reach the company or customer. |
| 5 | Waste generated in operations | Waste treatment from company operations. |
| 6 | Business travel | Flights, rail, hotels, taxis and other business travel. |
| 7 | Employee commuting | Employee travel to and from work, including home working where included. |
| 8 | Upstream leased assets | Emissions from leased assets not included in Scope 1 or 2. |
| 9 | Downstream transportation and distribution | Delivery and distribution after sale. |
| 10 | Processing of sold products | Further processing by another company. |
| 11 | Use of sold products | Customer use phase emissions. |
| 12 | End-of-life treatment of sold products | Disposal, recycling or treatment after use. |
| 13 | Downstream leased assets | Emissions from assets leased to others. |
| 14 | Franchises | Emissions from franchise operations. |
| 15 | Investments | Financed emissions from investments and lending. |
Category relevance by business model
| Business type | Likely priority categories | Why |
|---|---|---|
| Professional services | Purchased services, business travel, commuting, cloud and IT. | Direct emissions may be low, but travel and purchased services can matter. |
| Retailer | Purchased goods, transport, packaging, use of sold products, end-of-life. | Most emissions may sit in products and logistics. |
| Manufacturer | Purchased materials, capital goods, logistics, waste, product use. | Materials and downstream product impacts can dominate. |
| Software company | Cloud services, purchased services, employee commuting, business travel. | Operational footprint may be small but value-chain services matter. |
| Financial institution | Investments, purchased services, business travel, operations. | Financed emissions can outweigh operational emissions. |
How to screen categories
Start with a relevance screen. Ask whether the category exists, whether it is likely material, whether data is available and whether stakeholders expect disclosure. A software company may focus on purchased services, cloud, business travel and employee commuting. A manufacturer may need purchased materials, capital goods, logistics, product use and end-of-life treatment.
Calculation method options
Most companies use a mixture of methods. Spend-based calculations can provide a first estimate for purchased goods and services. Activity data can improve categories such as freight, travel, waste or fuel-related activities. Supplier-specific data can improve accuracy, but only if the method and boundary are clear.
| Method | Best for | Limitation |
|---|---|---|
| Spend-based | First pass screening across many suppliers. | Can be too generic for reduction decisions. |
| Activity-based | Travel, freight, materials, waste and energy-linked categories. | Needs better operational data. |
| Supplier-specific | High-impact purchased goods and strategic suppliers. | Quality varies and may not be comparable. |
| Hybrid | Most real-world inventories. | Requires clear documentation of each method. |
Do not chase false precision
First-year Scope 3 calculations often use a mix of supplier data, spend data, activity data and industry averages. That is acceptable if assumptions are documented. The goal is to improve data quality over time and use the inventory to drive decisions.
Improvement roadmap
- Year 1: screen all categories and estimate likely material ones.
- Year 2: improve activity data for the largest categories and engage key suppliers.
- Year 3: increase supplier-specific data, refine reduction actions and improve controls.
- Ongoing: update methods, record changes and focus reductions on the categories that matter most.
Which categories usually drive action?
Purchased goods and services often matters because it reflects what the company buys. Business travel can be easier to reduce quickly. Upstream and downstream transport can support logistics decisions. Use of sold products can be critical for equipment, vehicles, appliances or energy-using goods. Investments can dominate for financial institutions.
The best first category is not always the largest estimate. It is the category where better data and reduction action can change a decision. If purchased goods are huge but too broad, start with the largest supplier groups or material types. If travel is smaller but controllable, it may be a useful early reduction win.
Questions for each category
- Does the category exist for this business?
- Is it likely to be material by emissions, cost, customer concern or regulation?
- Do we have activity data, spend data or supplier data?
- Can we improve the data next year?
- Would calculating this category change a procurement, travel, design or strategy decision?
Minimum viable first inventory
A first Scope 3 inventory should screen all categories, calculate the categories most likely to be material and document the categories excluded from detailed calculation. That is better than calculating two easy categories and pretending the rest do not exist. The screen can be qualitative at first, as long as the assumptions are saved.
For an SME, a sensible first inventory might include purchased goods and services using spend data, business travel using activity data, employee commuting using a survey or assumptions, waste where records exist and transport where logistics data is available. The business can then improve the two or three largest or most decision-useful categories in the next cycle.
How to explain uncertainty
Scope 3 uncertainty is normal. The report should say which categories use supplier-specific data, which use activity data, which use spend-based estimates and which are excluded. This makes the inventory more credible, not less. Readers can see where the company is improving data quality instead of mistaking estimates for precise measurement.
FAQ
Do all companies have all 15 categories?
No. The categories are a screening framework. Some will not apply, some will be immaterial and some will need detailed calculation.
Which Scope 3 category is usually largest?
It depends on the business model. Purchased goods and services is often significant, but product use, logistics, investments or materials can dominate in specific sectors.
Should companies publish every category?
They should publish what is relevant to the reporting requirement and explain boundaries and omissions. Internally, it is still useful to screen all categories so exclusions are deliberate.