How do we count emissions from warranty replacements and spare parts we send to customers?
Parts you buy and send as replacements are purchased goods in Category 1; if you make them, their production energy is already in your Scope 1 and 2. Freight you pay to ship them is Category 4. Failed parts you take back and scrap go to Category 5 as waste.
Split the warranty cost by what happened
- Bought-in replacement parts: Category 1, by quantity or spend.
- Parts made in your own plant: already in Scope 1 and 2 through the plant's fuel and electricity; do not add them again.
- Courier or truck freight you pay: Category 4.
- Service engineers' travel: their vehicles if you own them are Scope 1; hired cabs and flights are Category 6.
Returned and failed parts
- Scrapped returns: Category 5, waste generated in operations.
- Repaired and resold units: the repair energy is in your Scope 1 and 2.
Use it as a signal
A high warranty rate means extra parts, freight and travel for the same product sold. Tracking warranty emissions next to the failure rate shows the carbon cost of quality problems.
What Senseible does here
Senseible reads purchase and service invoices; it uses quantities where the invoice shows them and otherwise gives a spend-based estimate, labelled as spend-based with wider uncertainty.
Sources: GHG Protocol Scope 3 Standard, Category 1 purchased goods and services, GHG Protocol Technical Guidance for Calculating Scope 3 Emissions (2013)
Last reviewed 2026-10-20.