Aer Lingus saw its passenger numbers rise to 1.26 million in July, a 4.3 per cent increase on the same month in 2014.
Short-haul route passengers grew by 37,000 passengers - 3.7 per cent - to a total of 937,000 for the month. Long-haul services saw an 18.3 per cent increase with 168,000 passengers.
According to RTE, Aer Lingus Regional, operated by Stobart Air, saw a decrease in passengers by 8,000, down to 134,000.
Load factor for the airline improved to 88.6 per cent, although it dipped slightly in its long-haul service.
So far in 2015, Aer Lingus has flown a total of 6.45 million passengers, a marginal increase on 2014.
This week, Ryanair announced that it flew over 10 million passengers in the month of July - more than Aer Lingus carried in the entire year of 2014.
