Passengers departing from Luton Airport faced longer delays than any other UK airport in 2017, it has been revealed.
On average flights left 19.7 minutes late from Luton, more than eight minutes later than Heathrow, which was the airport judged best for punctualityÂ based on Civil Aviation Authority data.
Birmingham, Durham Tees Valley, Jersey and Gatwick airports saw flights leave more than 18 minutes late on average.
Despite being one of the busiest airports in the world, Heathrow's flights are most punctual, with an average delay of 11 minutes, followed by Leeds Bradford, Belfast City, London City and Exeter - all under 12 minutes.
Glasgow was Scotland's best airport for punctuality, with flights leaving 15 minutes late, which, according to the Press Association, is the average across all UK airports.
Punctuality data enables passengers to "make informed choices about whichÂ airports they fly from", a CAA spokesman said.
"The aviation industry should constantly strive to improve punctuality to enhance the passenger experience," he added.
A spokesman for theÂ AirportÂ Operators Association (AOA) said "outdated" airspace infrastructure limits the efficiency of flights.
"The UK needs to modernise its airspace," he explained. "Airports are working with air traffic service providers and the Government to plan and deliver the necessary changes so everyone can continue to fly with a minimum of delays."
Here is the average delay for all departures from 25 of the UK's busiest airports in 2017, according to Press Association analysis of Civil Aviation Authority data.
1. London Luton 19.7 mins
2. London Gatwick 18.9 mins
3. Jersey 18.7 mins
4. Durham Tees Valley 18.6 mins
5. Birmingham 18.2 mins
6. Bristol 17.6 mins
7. Belfast International 16.7 mins
= Manchester 16.7 mins
= London Stansted 16.7 mins
10. Aberdeen 16.1 mins
11. Edinburgh 15.8 mins
12. Cardiff 15.7 mins
13. Glasgow 15.0 mins
14. Doncaster Sheffield 14.3 mins
15. Liverpool 14.0 mins
16. London Southend 13.5 mins
= Southampton 13.5 mins
18. East Midlands International 13.3 mins
19. Newcastle 12.8 mins
20. Bournemouth 12.3 mins
21. Exeter 11.9 mins
22. London City 11.6 mins
23. Belfast City 11.3 mins
= Leeds Bradford 11.3 mins
25. London Heathrow 11.0 mins