Airline easyJet has grounded its entire fleet of 344 planes because of the coronavirus pandemic.
Over the weekend several UK flights that were due to take off this week were cancelled.
Passengers were give the opportunity to change flights.
The Luton-based carrier said the measure "removes significant cost" as the aviation industry struggles to cope with a collapse in demand caused by the outbreak of the virus.
It insisted it "maintains a strong balance sheet" and revealed it is in "ongoing discussions with liquidity providers".
The airline also announced it has reached an agreement with union Unite on furlough arrangements for its cabin crew.
The deal will be effective from Wednesday, April 1 for a two-month period and means cabin crew will be paid 80% of their average pay through the Government job retention scheme.
Customers on cancelled flights can transfer to an alternative flight free of charge or receive a voucher for the value of their booking online or claim a refund through our contact centre.
A spokeswoman said: "We are experiencing higher than average wait times so we would thank customers for their patience and assure them that these entitlements will be available long after their cancelled flight has flown.
"For customers whose flights are not cancelled but would like to move to a later date they can amend their flight online with no change fee and we have brought forward our winter schedule on-sale so customers have more choice to move their flights, up to 28 February 2021.”
