New figures show a 3% annual increase in the number of passengers travelling between Shannon Airport and the US last year.
The CSO statistics also show strong growth on a number of key American routes.
Transatlantic visitors to Ireland are seen as some of the most important here, given that they typically stay for longer and thus spend more money.
Last year, just under 380,000 people flew through Shannon on journeys to the US, with New York's JFK Airport the most popular destination.
It also saw an increase of over 3,000 in the number of passengers on the route last year.
Boston saw a similar increase, while over 11,000 more people flew between Shannon and Philadelphia.
However, falls were recorded in the number of passengers to Newark and Chicago Airports.
Despite this, 2015 saw a near 3% increase in the number of people flying from Shannon to and from the US.
Authorities at Shannon will hope for a further hike in US-bound passengers this year, should Norweigian Air International secure a licence to operate its planned service to Boston.
A deal is in place with the airline for the flight, who are waiting for permission from authorities in the US.
