Since its opening, Shannon Airport has played a key role in seeing off transatlantic flights. It is also one of the few airports in the world that offers US Pre-clearance, the service allows passengers bound for the US to complete all of their immigration and customs declaration before their departure from Ireland.

Shannon was the first airport outside of the US to offer this sort of service, which made it an important stopover for US-bound flights from the 1980s. Passing through customs and immigration before landing in the US is extremely convenient, especially considering the queues found at large and busy airports on America’s eastern seaboard.

The preclearance service is well thought out, and passengers are considered domestic arrivals upon landing. If you have booked a flight from Shannon to an onward destination in the US heartland, your bags will be checked through to your final destination. While inbound passengers from other cities are queuing for immigration, collecting their bags and checking into another flight, you’ll be in the air and on your way.

There are few regulations that have to be satisfied prior to departure. First of all, passengers planning on travelling to the US with a visa waiver have to apply for travel authorisation online through the US Customs and Border Protection’s Electronic System for Travel Authorization. Furthermore, all of the preclearance formalities must be completed at least an hour before the flight departs. This means US-bound passengers need to show up well in advance of their scheduled departure time.