Aer Lingus carried a total of 1.148 million passengers last month, a two per cent increase on the same month last year.
The rise - up from 1.125 million in June 2104 - includes its regional services operated by Stobart Air. The airline's "mainline" traffic rose by 3.5 per cent, according to RTE.
Long-haul traffic increased by 15.6 per cent to 163,000 while short-haul also saw a slight increase of 1.5 per cent. Load factor- the amount of seats sold on each flight - only increased slightly from 85.5 per cent to 85.8 per cent.
Aer Lingus regional service, operated by Stobart Air dropped by 9.2 per cent to 118,000 passengers, the only marked decrease for the airline compared to last year.