EasyJet is adding 400,000 seats with extra flights from London-area airports next summer.
Turkey and the Canary Islands will receive the largest increases in capacity.
Turkish routes, including Antalya, Dalaman, Bodrum and Izmir, will gain an extra 230,000 seats.
The budget carrier claims to be the largest operator from London to Turkey’s beach destinations for summer 2020.
Return fares to Bodrum start at £55.98 and £81.99 to Antalya.
An extra 60,000 seats have been added to Tenerife, Fuerteventura and Lanzarote.
Additional flights have also been scheduled to summer destinations including Rhodes, Palma, Catania, Paphos, Marrakech and Larnaca.
The expansions follows the relaunch of easyJet Holidays last month.
The operator said it is targeting more than one million package customers in its first year.
UK country director Neil Slaven said: “Operating from London Gatwick, Luton, Stansted and Southend means we already offer customers flying to and from London an extensive range of destinations conveniently served across the city.
“It is great to be able to add to that in offering them more choice and great value on existing favourite summer holiday destinations.
“The addition of these extra seats on some of the most popular routes is great news for those booking their summer holidays.”
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