Almost 30m people flew in and out of Ireland's main airports last year - the largest number since the record in 2008.
Dublin was by far the busiest, accounting for almost 84% of travellers, while Cork and Knock were the only airports not to increase their numbers on the previous year.
The figures from the Central Statistics Office (CSO) show a 12.5% increase in air passengers at the main airports in 2015.
Almost 232,000 flights were handled by the five main airports, with Dublin accounting for 188,771 and Cork dealing with 17,910.
And cementing its slot as one of the world's most travelled routes, services over the Irish Sea from Dublin to London's Heathrow, Gatwick and Stansted were the busiest.
Out of Cork, the most popular routes were to Heathrow, Stansted and Amsterdam, while in Shannon the main routes were to Heathrow, Stansted and New York's JFK.
Stansted, Luton and Liverpool-John Lennon were the most popular routes to and from Knock.
A comparison with the record 2008 numbers shows Dublin has grown its share of the 30 million passenger market from 75% to almost 84%, while Cork is down from 10% to about 7%.
Shannon is down from 9% to almost 6%, Knock bucked the trend outside the capital growing by 0.3% to 2.3%, while Kerry still accounts for 1% of air travellers.
The CSO also said flights in and out of Ireland are most likely to be coming from or going to the UK, Spain and the US.