Flights to Alicante, Fuerteventura and Lanzarote (Arrecife) are all at risk of delay, said Jet2.com, due to action on Monday (6 February).
In an update issued late on Tuesday (31 January), Jet2 said: "We wanted to let you know that industrial strike action is taking Monday 6 February, supported by the air traffic service in Spain. This means that flights operating to Alicante, Fuerteventura and Lanzarote (Arrecife) may be delayed.
"If you’re affected, rest assured we’ll try to keep any disruption to a minimum. Please arrive at the airport at least two hours before your departure time. Check-in closes 40 minutes before a flight’s scheduled departure time.
"For up-to-date information, please check this web page again, as well as the departure screens and listen out for any announcements. We’ll have you on your way as soon as we can."
It comes after Jet2 issued a like warning for flights to France, or flights using French airspace, between Monday 30 January and Wednesday 1 February, again owing to ATC strike action. The action was due to end at 5am GMT on Wednesday.