AER Lingus said passenger numbers in the quarter ended March 2012 rose by 8.2pc to just over 2.08m compared with the same period last year.
The airline carried a total of 809,000 last month.
The number of long-haul passengers rose by 12pc to 167,000 in the quarter.
Short haul numbers were up by 6.2pc to 1.7 million.
The passenger load factor also increased this month to 78.8pc – with the sharpest increase in long-haul.