The Hungarian carrier’s UK departures were an average of 14 minutes and 24 seconds behind schedule in 2021, according to analysis of Civil Aviation Authority (CAA) data by the PA news agency.
It operates short-haul flights from 10 UK airports including Belfast International, Cardiff, Edinburgh, Gatwick and Luton.
Tui Airways recorded the second worst punctuality, with an average delay of 13 minutes and 18 seconds.
This was followed by British Airways (12 minutes and 42 seconds) – including its subsidiary BA CityFlyer – Virgin Atlantic (12 minutes) and Loganair (11 minutes and 30 seconds).
The two most used airlines by UK passengers, easyJet and Ryanair, were among the leading performers in terms of punctuality.
EasyJet had the second shortest average delay per flight of four minutes and 36 seconds, while Ryanair was in third place with six minutes and six seconds.
Only Ireland’s flag carrier Aer Lingus performed better, with a typical delay of just three minutes and 12 seconds.
The analysis took into account all scheduled and chartered departures from UK airports by airlines with more than 2,500 flights. Cancelled flights were not included.
The average delay was eight and a half minutes per flight.
Analysis by PA conducted earlier this summer found that Birmingham was the UK’s worst airport for flight delays last year.
Punctuality across the aviation industry in 2021 was better than before the coronavirus pandemic due to the reduction in flights caused by travel restrictions.
But the situation has deteriorated this year, with staff shortages causing major problems for several airports and airlines, leading to tens of thousands of flights being cancelled.
Guy Hobbs, editor of consumer magazine Which? Travel, said: “While these findings are worrying, the reality has actually been far worse for many travellers this summer.
“Holidaymakers have faced a barrage of disruption over the last few months, and these latest figures only serve to underline the need for urgent reform of the travel industry.
“The Government must drop plans to slash passenger compensation for delayed and cancelled domestic flights.”
Paul Charles, chief executive of travel consultancy The PC Agency, said: “Worsening flight delays have caused enormous stress to many consumers over the last year, as well as financial pain while waiting for refunds and compensation.
“Airlines, airports and air traffic control teams need to work together far more closely and ensure that flying becomes more seamless and more enjoyable for us all.
“That will only happen when staff shortages are properly overcome and the aviation industry can grow again post-pandemic.”
Wizz Air was approached for a comment.
Wizz Air is the eighth largest airline operating in the UK, with flights to 74 destinations in 23 countries from nine airports. It was recently named one of the top 10 best value airlines for flying short haul based on ticket price.
In 2019 it commenced connections from Edinburgh, with flights to the Polish cities of Warsaw and Gdansk, as well as Budapest in Hungary and Bucharest in Romania.
These new services were expected to see an increase in capacity of 250,000 seats on theairline’s Scottish routes