Easyjet will run “rescue” flights and may put bigger planes on busy routes to deal with the after-effects of strikes by French air traffic controllers.
The airline cancelled 248 flights on Wednesday and 340 flights on Thursday, making it one of the operators worst hit by the two-day strike.
No cancellations were expected on Friday, but Easyjet said some affected passengers still needed flights.
Two more stoppages are expected in the coming weeks.
French air traffic controllers have scheduled the first from 16 April to 18 April and the second from 29 April to 2 May.
Call centre hours
Some passengers have been stranded in European cities after Easter breaks following the latest strike, prompting Easyjet to operate five “rescue” flights on Friday.
The flights will bring three parties of schoolchildren back to the UK.
The additional flights will run from Luton to Paris, Paris to Barcelona, Barcelona to Luton, Gatwick to Madrid, and Marrakech to Gatwick.
“EasyJet recognises that there are a number of passengers across the network who have been affected by these cancellations and still require flights as soon as possible,” a spokesman said.
The airline said it was extending opening hours of its call centres to help those who still needed to rearrange travel. It said it took 13,000 calls on Wednesday and 12,820 calls on Thursday.
Some other airlines were affected by the strike action on Wednesday and Thursday, which affected flights to and from France, as well as flights over French airspace.
Ryanair said it had been forced to cancel more than 500 flights over the past two days.
A spokeswoman for the airline said: “All operations are running as normal. All customers affected by the two-day ATC strike have been contacted and advised of their options.”
Among those affected were Nathan Thorne, 23, from Goole on Humberside, and his sister Olivia, 14, who had their Ryanair flight from Limoges to Leeds Bradford cancelled on Thursday.
Mr Thorne, who is with the army’s Royal Logistics Corps, is anxious to get back as he begins a six-month tour of duty in the Falkland Islands on 22 April. His sister needs to get back for school on Monday.
“All the flights before next Thursday are booked up and the Eurostar train is extremely expensive,” he said.
Short-haul and medium-haul flights operated by Air France were also affected by the strike.