Jet2 announces new Glasgow routes to Costa de Almeria and Krakow
The airline will also base an eighth aircraft in Scotland's biggest city this summer, with overall capacity being increased by 30 per cent to 1.3 million seats.
That will be the most Glasgow-based aircraft of any airline.
The new routes brings Jet2's total from Glasgow to 34, with up to 220 flights a week.
The new flight to Costa de Almeria in Spain will operate on Sundays between May and the end of October.
Twice-weekly services to Krakow in Poland will be on Mondays and Fridays.
The expansion will come as a second major boost to the struggling airport following The Scotsman's revelation last week that Emirates would fly the world's largest passenger plane year-round to Dubai.
Glasgow, which does not publish its passenger figures, was down 8.7 per cent to 8.9m in the year to last November, according to the Civil Aviation Authority.
The extra flights are to the Balearics, Canaries, Turkey, Greece, Spain, Bulgaria and Portugal between mid-June and mid-July.
Palma, Majorca flights will be increased by two to up to 13 a week
Menorca will go up one to up to three.
Tenerife increases by one to up to seven.
Fuerteventura goes up one to up to three.
Malaga gets one extra, to total up to seven.
Alicante is up one to up to ten.
Corfu is doubled to two.
Heraklion in Crete is up one to up to four.
Dalaman goes up one to up to six.
Antalya gets an extra weekly flight, taking it up to five.
Faro is up one to up to seven.
Bourgas in Bulgaria is doubled to two.
Jet2 chief executive Steve Heapy said: “This expanded programme has come in response to the continued demand for our award-winning flights and holidays from customers in Glasgow.
"Over 300,000 additional seats, additional aircraft, and two brand new destinations represents significant growth at the airport."
Glasgow Airport managing director Mark Johnston said: “Jet2.com’s decision to introduce an additional aircraft during our peak season is tremendous.
"There continues to be huge demand for our most popular sun destinations and the 20,000 extra seats this aircraft brings will be welcome news for our customers looking to book their summer 2020 holidays.”
But campaigners Flight Free UK, which asks people to pledge not fly in 2020, said aviation was not sustainable.
Director Anna Hughes said: "We simply cannot continue to expand the aviation industry at a time of climate crisis.
"All of the science tells us our reliance on fossil fuels must end if we are to stand a chance of reaching our emissions reduction targets.
"The aviation industry already accounts for roughly 10 per cent of UK emissions, which will only continue to grow as airlines provide ever more routes - a worrying trend at a time when we need to be drastically reducing our emissions."