Aer Lingus passenger numbers grew by 7.6 per cent in June 2008 to 958,000 people compared with the same month the pervious year.
The load factor, or proportion of seats filled, fell to 81.5 per cent from 82.2 per cent a year earlier, the airline said in a statement today.
The increase in passengers came in the context of 12.8 per cent increase in capacity.
Passenger numbers on short-haul flights rose 7.8 per cent to 831,000 while those on long-flights grew by 6.7 per cent to 127,000.
On short-haul flights the load factor fell slightly to 81.1 per cent compared with from 81.6 per cent last year, while the long-haul load factor was also down slightly, to 82.1 per cent from 83 per cent.
Davy analyst Ivan Skelly said the relatively small drop in the load factor in the context of a significant increase in capacity was a "strong performance by the airline"
At 2.45pm Aer Lingus shares were trading 2.6 per cent up at €1.27. Over the year-to-date the airline has seen its share value fall almost 40 per cent, giving it a market cap of €677 million.
Earlier today oil prices fell by over $3 a barrel to €141.
Earlier today, EasyJet has said its passenger numbers rose by 19.5 per cent over the year to June with a load factor rising slightly to 86.9 per cent.
EasyJet said today that 70 per cent of seats for the second half of the year ending September 30th have already been sold.