Flights to and from Luton were suspended on Tuesday evening (10 October) and will remain grounded until at least 3pm on Wednesday, the airport has said.
Images and footage from the scene showed flames leaping from the upper floors of Terminal Car Park 2 during the night, leaving a burned out shell come the morning.
At its height, more than 100 firefighters were in attendance, along with three aerial platforms and support from local police and ambulance crews.