The airline and operator is understood to have around 1,000 staff based at airports in Spain and its islands.
Jet2 currently flies to six destinations in mainland Spain, including Alicante and Malaga, four in the Canary Islands and three in the Balearics.
According to local media reports in the Canaries, Jet2 has entered into a 30-day period of negotiations with union officials in Spain, which could see up to 35% of affected roles made redundant.
The proposed job cuts span the airline and operator’s resort flight check-in service, flight deck and cabin crew.