Wizz Air said the number of passengers using its services in December plummeted by 80% compared to the year before, to 665,722.
The airline's available seats were 1.1mln, 68% lower than December 2019, while its load factor stood at 56.1% compared to 89.4% the year before.
Competitor Ryanair didn't fare much better, with traffic crashing 83% to 1.9mln guests, as it operated only 22% of the normal December schedule with a 73% load factor.
Wizz Air also announced six additional new routes between Doncaster Sheffield, Gatwick and London Luton bases and destinations in Turkey, Bulgaria, Spain and Greece.
The budget airline said it operates at the lowest CO2 emissions per passenger/kilometre amongst all competitor airlines, with 67.1 grams per passenger/kilometre over the whole of 2020.
For the month of December, emissions were 44% higher than last year due to the drop in load factor, while total CO2 emissions in tonnes decreased at a slightly higher rate than capacity.
Ryanair dipped 1% to €15.24 while Wizz Air remained flat at 4,466p on Monday morning.
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