Aer Lingus has resumed its service between Dublin and San Francisco, with connections to Heathrow, Gatwick, Birmingham, Manchester, Edinburgh and Glasgow airports.
Further UK connections from Bristol and Leeds will be added from April 15, with UK residents able to pre-clear US immigration in Dublin.
The San Francisco service will begin four times a week, before moving daily from March 26.
Bill Byrne, the airline’s executive vice-president US, said: “We are delighted to resume our Dublin to San Francisco service.
“With the convenience of US Customs and Immigration pre-clearance at Dublin, time spent connecting through Dublin provides customers with a speedier journey overall, as they arrive in the US as a domestic passenger.”
In addition to San Francisco, more US West Coast services are due to restart in the coming months, with daily flights to Los Angeles beginning on May 12 and flights to Seattle returning five times a week from May 26.