More than 7.6 million trips were made to Ireland last year, according to the Central Statistics Office, up 8.9% on the same figure for 2013.
More than 41% of those trips - or 3,163,900 - were made by residents of Britain, up more than 8% on 2013 figures.
A further 15.4% - 1,169,100 - came from the United States, up 12.9% year-on-year.
Trips by German residents was also up, rising by 15.4% to 557,200.
Almost 1.7 million of all trips last year were made in the last three months of 2014, up 7.3% on the same period of the previous year.
Close to half of the quarter's trips - 768,100 - were made by residents of Britain, which was 5.6% higher year-on-year.
Residents of other European countries accounted for a further third of the total at 559,000, which was a 6% rise on the same three months of 2013.
Trips by residents of North America accounted for more than 15.5% of the total at 264,100, but this represented a 18.2% rise on the previous year's final quarter.
Trips by residents of other areas - including Asia and the Middle East - rose by 1.7% to 103,700.
