Aer Lingus passenger carryings remained flat in May at 882,000 over the same month last year.
Short-haul numbers were down by more than 1% to 793,000 while long-haul carryings grew by 12.7% to 89,000.
The Irish carrier’s regional passenger numbers, reported separately, rose by 33.3% to 88,000.
Total flown passenger numbers, including Aer Lingus Regional operations, increased by 2.4%.
The overall passenger load factor increased by 2.9 points on May 2011 to 76.2%.
Short-haul load factor was 73.8%, an increase of 0.9 points on May 2011, with capacity down by 1.6%.
The long-haul load factor was 81.5%, an increase of 7.4 points on May last year, with capacity increasing by 0.5%.