Long-haul flights (economy): carbon footprint per passenger-km (with RF)
Live factor value
0.11704 kgCO2e per passenger-km (with RF)
Source: UK DESNZ greenhouse-gas conversion factors, 2026 (revision 2). Factor set desnz-2026-r2.
Long-haul flights have a lower per-km factor than short-haul — the fuel-hungry take-off is spread over thousands of cruise kilometres — but the distances are so large that a single long-haul trip usually dominates a personal annual footprint. The official DESNZ 2026 economy factor is shown live below, radiative forcing included.
A London–New York economy return comes to roughly 1.4 tonnes of CO2e on this method — about a quarter of an average UK resident's entire annual footprint. Premium cabins multiply the figure: a business-class seat roughly triples it.
Worked example
London to New York, one way (~5,576 km GCD + 8%): 6,022 × 0.11704 = 705 kgCO2e.
Measure your own with the free travel calculator.
Frequently asked questions
- How much CO2e is a London–New York return flight?
- About 1,400 kg CO2e per passenger in economy, using DESNZ 2026 long-haul factors (0.11704 kgCO2e per passenger-km with RF) on the great-circle distance plus 8%.
- Why does business class have a bigger footprint?
- A business seat occupies the space of roughly three economy seats, so each passenger carries a larger share of the aircraft's emissions. DESNZ publishes separate per-cabin factors for this reason.