The budget airline said following the collapse of Monarch, competitors had not snapped up the empty slots overlapping easyJet capacity as quickly as anticipated.
It added the positive outlook came despite industry-wide disruption in Europe impacting revenue, costs and operational performance, driven by industrial action and air traffic restrictions.
On Wednesday (July 18), easyJet reported total third quarter revenue (three months to June 30) rose to £1.6 billion, up 14%), while ancillary revenue increased 21.1% to £328 million.
Passenger numbers increased 9.3% to 24.4 million against capacity of 26.2 million seats, boosting its load factor 0.3% to 93.4%. Revenue per seat is up 4.8%.
As a result, EasyJet has raised its annual profit guidance from £530 million to £580 million to £550 million to £590 million.
Johan Lundgren, easyJet chief executive, said: "easyJet has delivered strong performance during our third quarter, driven by robust customer demand.
“We have also seen continued growth in ancillary revenues, mainly due to more passengers choosing to buy allocated seating and hold bags.
“With easyJet on track for a positive summer trading period during the fourth quarter, we are raising our guidance for full year headline profit before tax for financial year 2018.”
However, easyJet sounded one note of caution after its fledgling operations at Berlin’s Tegal airport got off to a weaker start than expected, with the airline expecting total associated losses to come in at £175 million rather than £160 million.
It has though said it expects to break even on its Berlin operation during the 2019 financial year.
Factors impacting Q3 performance included “sustained ATC industrial action in France” and the “impact of severe weather”.
EasyJet was forced to cancel 2,606 flights during Q3 compared to just 314 during the same period last year.
On the Monarch situation, EasyJet said: “Current data shows uptake by competitors of overlapping Monarch capacity continues to be lower than expected into Q4, however, some impact on late yields may be expected from continued warm weather.”
Ancillary revenue, derived fromg allocated seating and baggage charges, is up 16.3% year-on-year from £271 million to £315 million at a rate of 11.5% per seat, with EasyJet attributing some of the improvement to “improved website functionality”.