Ryanair will begin flying year round from Knock airport in Co Mayo to Birmingham in the English midlands from next March.
Jason McGuinness, the carrier’s director of commercial, said the airline would add the route as part of its summer 2022 schedule.
Mr McGuinness said Ryanair had added 560 new routes and 16 bases to its network over the past 12 months.
The carrier will add 65 new Boeing 737-8200 aircraft to its fleet by next year, which have more seats and burn less fuel than previous models of the jet.
Knock airport noted that the route was the third new service from there announced by the airline this year, following Edinburgh and Manchester.
Joe Gilmore, Knock's managing director, welcomed the news. "Our Birmingham service has long been one of our most established routes from the airport and it has been a priority for the airport to see this popular service restored," he said.