A passenger's share of a flight's emissions is not always allocated equally. Business and first-class seats use substantially more floor area than economy seats, reducing the number of passengers carried for the same aircraft movement.
How cabin allocation works
A flight emissions calculation starts with fuel burn and adjusts for route, aircraft, freight, load factor and other factors. The passenger share is then allocated across occupied seats.
Cabin multipliers account for the greater space used by premium seats. A lie-flat business seat may occupy several times the floor area of an economy seat, so the passenger is assigned a larger share of the aircraft's emissions.
Why the exact multiplier varies
The result depends on methodology and route. Short-haul business class may use the same physical seat with an empty middle position. Long-haul cabins can have much larger differences in seat pitch and width. Cargo allocation and non-CO2 aviation effects can also change the final number.
This is why a single universal multiplier should be treated as an approximation rather than a physical constant.
Corporate accounting implications
Business travel is Scope 3 Category 6. Companies should use consistent calculation methods, retain flight and cabin data where available and focus reduction policies on the highest-impact routes and traveller groups.
Levers include rail substitution, virtual meetings, travel approval rules, economy-class policies and fewer but longer combined trips. Carbon credits may support a beyond-value-chain contribution, but they should not replace travel reduction and procurement changes.
Our emissions advisory service helps companies build auditable Scope 3 inventories and prioritise practical reduction levers.
