Do I have to report all 15 categories?

No. Under PPN 006 and GHG Protocol, you report categories material to your business and explain exclusions.

Scope 3 Emissions: A Guide to Deliveries, Waste & Business Travel

Q: What are Scope 3 emissions?

Scope 3 emissions are all indirect greenhouse gas emissions in a company's value chain not covered by Scope 1 or 2. They typically represent 70–90% of a business's total carbon footprint.

Q: How many Scope 3 categories are there?

The GHG Protocol defines 15 Scope 3 categories, split into upstream (1–8) and downstream (9–15). Most UK SMEs report on 4–7 material categories.

By Frazer Holroyd · 14 min read · Carbon Basics · February 2026

Scope 3 emissions represent 70–90% of most business carbon footprints, yet they're the most misunderstood and difficult to measure. This guide explains how to measure the most common Scope 3 categories for UK businesses using GHG Protocol methodology and DEFRA emission factors.

What Are Scope 3 Emissions?

Scope 3 covers all indirect emissions in your value chain not covered by Scope 1 (direct) or Scope 2 (purchased energy). The GHG Protocol defines 15 categories, split into upstream (1–8) and downstream (9–15). Most UK SMEs focus on 4–7 material categories.

Key Categories for UK Businesses

Category 4 — Upstream Transportation: Inbound deliveries from suppliers. Calculated using weight × distance × DEFRA vehicle emission factors.
Category 5 — Waste: Emissions from waste disposal. DEFRA provides factors by waste type and disposal method (landfill, recycling, incineration).
Category 6 — Business Travel: Flights, rail, taxi, and personal car use. DEFRA factors vary by cabin class and transport mode.
Category 7 — Employee Commuting: Staff travel to work. Calculated from commuting surveys or postcode-based distance estimates.
Category 9 — Downstream Transportation: Outbound deliveries to customers.
Category 1 — Purchased Goods: Often the largest category. Spend-based or activity-based methods available.

Data Collection Tips

For deliveries: request weight, distance, and vehicle type from logistics providers. For waste: collect waste transfer notes showing tonnage by waste stream. For business travel: use expense reports and booking systems. For commuting: employee surveys with postcode and transport mode data.

Frequently Asked Questions

What are Scope 3 emissions?

All indirect emissions in your value chain not covered by Scope 1 or 2. Typically 70–90% of total footprint.

How many categories are there?

15 categories defined by GHG Protocol. Most SMEs report 4–7 material categories.

Do I have to report all 15?

No. Report material categories and explain exclusions.

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