Commercial airlines worldwide - passenger load factor 2005-2021

The combined passenger load factor of global airlines has been gradually trending upwards over the last 15 years; from 75.2 percent in 2005, in 2019 the passenger load factor was around 82.5 percent.

Passenger load factor

Passenger load factor (PLF) is a measure of how much of an airline’s passenger carrying capacity has been utilized. It is calculated by dividing the revenue passenger kilometers, which is the total number of kilometers flown by passengers, by the available seat kilometers, which is the total number of kilometers flown for every seat in an aircraft (regardless of whether it has been filled or not). A higher passenger load factor therefore means that there are less empty seats on each aircraft, but does not indicate anything about changes in the total number of kilometers flown per passenger or per seat .

PLF and profitability

As airlines have fixed costs associated with every flight, a higher PLF will generally mean a higher profit margin for airlines. PLF is only one factor affecting total profitability though, meaning increases in PLF do not necessarily correspond with higher profits. In particular, the cost of airline fuel, which can be highly variable, has a strong effect on the operating margin of airlines. This can be seen clearly in through the jump in profitability from 2014 to 2015, which corresponds with a steep drop in the expenditure required for fuel.