Local bus travel: carbon footprint per passenger-km
Live factor value
0.12552 kgCO2e per passenger-km
Source: UK DESNZ greenhouse-gas conversion factors, 2026 (revision 2). Factor set desnz-2026-r2.
The official emission factor for local bus travel outside London is published per passenger-km in the DESNZ 2026 conversion factors and shown live below. It reflects average diesel-dominated fleets and average occupancy across the country.
A bus journey is typically less than half the per-km footprint of driving alone, and the factor will keep falling as electric buses replace diesel fleets. For London buses, TfL's newer fleet means a somewhat lower figure than the national average shown here.
Worked example
A typical 8 km bus commute (one way): 8 × 0.12552 = 1 kgCO2e.
Measure your own with the free commuting calculator.
Frequently asked questions
- How does the bus compare with driving?
- On official averages, a bus passenger's per-km footprint is well under half that of a lone driver in an average car — the advantage grows the fuller the bus.