Figures from the Central Statistics Office show that the number of trips made by Irish people abroad in the first quarter of this year was down 13% on the same period last year.
The figure fell to 1.54m, in what the CSO said was the first such drop since 2000.
The biggest fall was in trips to continental Europe - down 17% - but trips on cross-channel sea routes were up 1%.
The number of visits to Ireland in the first quarter was just over 1.4m, a fall of 9% on the same period last year, though the CSO points out that this was influenced by the timing of Easter. Easter fell in March last year, but in April this year.
The biggest drop was in the number of British visitors, down 15%, while trips from north America fell 9%. But trips from continental European countries were up 2%.
The number of bednights spent by overseas visitors in Ireland dropped 12% from a year earlier, with nights spent in hotels down 20%.
The CSO figures also show that the amount of money spent by Irish people abroad in the first quarter was €1.3bn, while earnings from visitors to Ireland were €694m.