Aer Lingus will introduce a new product on short-haul flights from September.
Branded Aerspace, it will have four seats available per flight, guaranteeing a seat in the first-row window or aisle with an unoccupied middle seat.
Passengers will also get reserved overhead cabin space, a checked 20kg bag, lounge access, fast-track at security, priority boarding, and a free snack and beverage onboard.
Aer Lingus said it would be a unique offering in Europe.
The Irish flag carrier’s most popular short-haul routes are London, Paris, Manchester and Barcelona.
It currently offers pay-to-enter lounge access at Dublin, Heathrow and JFK for €30 (£25).
Susanne Carberry, Director of Network Revenue and Loyalty, commented: “We are thrilled to introduce a new fare option which gives greater comfort and convenience to our guests.
“At Aer Lingus we are committed to innovating our product offering to meet travellers’ ever-changing needs. AerSpace guests will have reserved seating in row 1 on our most popular routes, leaving the middle seat free and allowing more space to work or simply relax as they fly.
“We are proud to launch AerSpace in response to feedback from our guests seeking a more premium and spacious travel experience when flying short haul with Aer Lingus.”