Wizz Air achieved record August carryings of more than four million passengers on the back of fleet expansion.
Rival Ryanair saw passenger numbers grow by 8% in August to 14.9 million across the group.
The summer peak month led to a 16.1% year-on-year rise in Wizz Air’s passenger numbers.
The Hungarian budget airline achieved a load factor of 96.3%, a rise of 0.7 percentage points over August last year.
The carrier’s fleet rose to 119 aircraft in the month with the addition of two Airbus A321ceo aircraft.
Wizz Air announced 23 new routes, including eight from the UK from new bases at Edinburgh and Southend airports.
CO2 emissions for August were 2.1% lower than the same month last year, at 56.1 grams per passenger/km.
Last month’s figures gave the airline a rolling 12 month total up by 17.8% to 60.8 million.
Ryanair accounted for 14.3 million of the group total, with Austrian offshoot Lauda providing 600,000.
The Irish budget giant operated more than 81,000 scheduled flights in August with a load factor of 97%.