EasyJet PLC (LON:EZJ) posted higher passenger numbers in May but flagged a hit from air traffic control strikes.
The Luton-based budget airline said it carried 6,861,040 passengers during the month, up 5.7% from 6,490,974 a year ago.
But its load factor - a measure of how full its aircraft were - fell 0.1 percentage points to 91.5%.
In the 12 months to May, passenger numbers rose 7.3% to 71,495,087 and the load factor increased 0.2 percentage points to 91.4%.
Both airlines have blamed air traffic control (ATC) strikes in France and Italy for disruption, but easyJet also highlighted bad weather and the Brussels terror attacks.
In May there were 173 cancellations for the month, with French ATC strikes and weather conditions accounting for most of those, easyJet said.
It also pointed this month to the Egypt air tragedy on May 19.