Holidaymakers have been advised to get to the airport three hours before their flight home due to European border checks.
Queues at airports have seen severe delays in recent months due to the EU’s Entry Exit System (EES).
The system requires passengers to provide fingerprints and other information upon arrival, which is then checked when they leave.
Greece has already waived the EES for British travellers to avoid serious disruption over the summer holidays.
The boss of Wizz Air warned that some holidaymakers have missed their flights due to the rules.
Yvonne Moynihan advised getting to the airport hours earlier to avoid the worst of the travel chaos.
She told the BBC: "When you land in the destination airport, there might be queues, so you should bring a portable charger or water.
"Because there is another passport check... that's where we see that people have, again, experienced longer waiting times than anticipated.”
Ms Moynihan added that although it was usually enough to get to the airport two hours before a flight, "in these circumstances, we are advising three hours".
It comes after a survey found that nearly three out of five (59 per cent) of UK holidaymakers travelling to Europe this year expect delays linked to the EES.
Almost half of respondents to the poll commissioned by travel company Booking.com said they fear missing flights because of the border checks.
Representative body Airports Council International recently reported that EES was causing delays of up to three hours, with airports in Spain, Portugal, France and Italy among the worst affected.
More than 100 easyJet passengers missed a flight from Milan Linate to Manchester last month because of delays at passport desks caused by the ramp up of EES.
The survey indicated that 56 per cent of UK travellers plan to arrive at airports earlier than usual in an attempt to avoid disruption, with 12 per cent intending to arrive at least four hours before departure.
