Last year was the busiest year on record for Dublin, Cork and Shannon airports, with almost 18 million passengers travelling through the three facilities, according to Aer Rianta.
Dublin took the vast majority of the traffic, with 13.8 million, an increase of 8% on 1999.
Shannon had the next biggest slice at 2.4 million, a 10% rise from the previous year. But Cork showed the largest percentage increase, up 12% to 1.7m passengers.