The works have been going on at the north east France airport since November 2018, but now airport bosses say they have no choice but to close completely for two days in August to allow works to be done on the main runway.
There will therefore be no flights taking off or landing at Lille between 11pm on Monday, August 5th and 2pm on Wednesday, August 7th.
Flights for those days are being diverted to either Ostend in Belgium or Charles de Gaulle airport in Paris.
The airport operators are offering free shuttle buses to ferry people to and from the diverted airport, but at 223km to Paris or 72km to Ostend, that will add significantly to journey times for flights.
For example anyone booked on the 6am flight to Varna, Bulgaria, will have to depart from Lille airport in the shuttle bus at 00.30 in order to get to Paris CDG in time to catch their flight.
Lille airport bosses apologised in advance to passengers for the disruption, but said that August was the most appropriate month to carry out the closures.
For a full list of the flights affected, and the timetable of the shuttle bus alternative, click here.
The site warns that some details are subject to change, so we would suggest that people check again nearer to their flight date.