EASYJET raised its guidance after its revenue per set grew following the collapse of Thomas Cook.

The company also said that new initiatives to sell more luggage space, and allocated seats, as well as offering car rentals from a partner, helped push up revenue.

It said it expects its first half performance to improve from last year on the back of strong travel demand and less competition following Thomas Cook’s closure.

The company said 22.2 million passengers flew on its planes in the first quarter, an increase of 2.8 per cent compared with the same period a year earlier.

Passenger revenue grew 9.7% to £1.1 billion.

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The company announced expansion plans for Scotland in December, including a ninth Airbus A320 aircraft will be based in Edinburgh and five new routes will serve both Edinburgh and Glasgow, but it did not have a performance breakdown for north of the Border for the quarter.

Johan Lundgren, chief executive, said the airline believes per-seat revenue grew by 1.5% because of the Thomas Cook - which went into administration in September - with overall revenue per seat increasing by 8.8% to £58.63 in the three months to December 31.

The load factor - the percentage of seats that were occupied - was 91.3%, an increase of 1.6 percentage points.

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The airline said 75% of its seats have been booked for the first half of the year, ending March 31, which is one percentage point ahead of the same time last year.

Mr Lundgren said: “I’m pleased that we have made a strong start to the year, with continued positive momentum. The improvement in our revenue per seat has been driven by our self-help revenue initiatives combined with robust customer demand and a lower capacity growth market.” Investors reacted positively to the news, sending shares in the company up 4.5%, rising 65p to 1,515p.

Sir Stelios Haji-Ioannou, the founder and largest shareholder, said his airline economics theory remains true: “That is when you grow the seats flown by only 1% year-on-year the revenue per seat goes up 9%.”