The US ended a year-long stand-off with Ireland and the EU by granting an operating licence for Norwegian Air International (NAI) to begin transatlantic services.
The move is now expected to spark a price war on transatlantic services - and offers Cork its long-awaited first transatlantic link.
The US Department of Transport confirmed the granting of a licence which will now allow NAI to start services from Cork to Boston early next year.
Fares will shortly be offered for a service which Cork Airport has been campaigning for now for more than 25 years.
The budget carrier also plans to launch a service from Cork to New York, most likely in 2018.
Cork Airport managing director Niall MacCarthy hailed the decision as "a great win for Open Skies" while Housing Minister Simon Coveney described it as "a landmark development" for Cork.
Cork Chamber of Commerce chief executive Conor Healy said the decision offered enormous potential economic benefits for both the city and entire region.
The decision came after the EU had signalled it was demanding independent arbitration on the US failure to grant an operating licence to NAI. Taoiseach Enda Kenny had also requested US President Barack Obama's help over the increasingly bitter row. The issue was even raised during the US election.