Passengers flying from Heathrow Airport are being charged an extra £8.90 due to the collapse in demand for air travel.
The airport said the fee is necessary to help pay for services such as baggage systems, lighting and check-in desks.
The huge reduction in passenger numbers means the costs are no longer being met by the usual charges paid by airlines.
Heathrow did not rule out raising the Airport Cost Recovery Charge to enable “full cost recovery” by the end of the year.
The airport recorded a loss of £1.5 billion in the first nine months of 2020.
Passenger numbers between July and September were down by more than 84% compared with the same period in 2019.
A Heathrow spokeswoman said: “Heathrow provides key airport services like the baggage system, colleague car parks, airline check-in desks and utilities for our partners to use.
“The fee to use these services is calculated purely to cover the cost of providing them – Heathrow makes absolutely zero profit from these services.
“To ensure this remains the case, the fee is closely monitored by the CAA (Civil Aviation Authority), as well as being scrutinised and agreed with airport users annually – as was the case with this year’s charge.
“The cost per passenger to cover these services naturally fluctuates depending on the number of passengers using the airport.”