The Fleet Air Arm lacked a truly outstanding fighter until the end of the war. But compared to the mediocre designs available at the start of the conflict, the Fairey Fulmar was rather decent and gave a good account of itself in the Atlantic and Mediterranean. Nevertheless, the large and heavy two-seat design was no match for the more nimble Japanese fighters in the Pacific which put the FAA at a great disadvantage until the introduction of the Seafire and lend-lease aircraft like the Corsair although ultimately, they remained in service in declining numbers until 1945. Fulmars were in action in the Battles of Taranto and Cape Matapan where they were used as escorts for the torpedo bombers, in the Atlantic launched from catapult-armed merchant (CAM) ships, and in the defense of Ceylon where they were hard pressed against the considerably superior Zero. They ended the war mostly as night fighters protecting Russian convoys and as deck landing trainers.

The first Fulmar prototype, developed from the Fairey P.4/34 light bomber prototypes, was flown on 4 January 1940 and entered production as the Mk. I. They were listed in the order of battle during the Battle of Britain but never engaged in combat. The Mk. II was a tropicalized variant and featured the Merlin XXX engine. It was the most widely produced, accounting for slightly over half of all examples.