Air Canada's improvement was led by flights to the U.S., Atlantic, Latin American and Caribbean markets.
The airline (TSX:AC.B) reported a load factor of 85.7 per cent, up from 85 per cent in June 2013, including subsidiary Air Canada Rouge and regional airlines from which it purchases capacity.
The increase came as Air Canada's traffic, measured by revenue passenger miles, increased 10.6 per cent, surpassing a 9.8 per cent increase in capacity, measured by available seat miles.
Meanwhile, WestJet (TSX:WJA) reported a load factor of 77.4 per cent, up from 76.8 per cent a year ago.
WestJet's traffic increased five per cent, while its capacity went up only 4.3 per cent.