UK flight delays and cancellations make headlines whenever a heatwave, storm or strike disrupts the school holidays, but the full picture is more reassuring than a handful of bad news stories suggest. The Civil Aviation Authority (CAA) publishes monthly punctuality statistics for every major UK airport, covering cancellation rates and how early or late departures actually run. We have analysed this dataset to answer the questions travellers ask most: which UK airports cancel the fewest flights, which ones run early, and what “on time” actually means in aviation terms.
How the CAA measures flight punctuality
The CAA defines a cancelled flight as a previously planned service that does not operate, announced less than 24 hours before or after its scheduled departure. Punctuality itself is measured by comparing the actual gate time, meaning the off block time on departure or on block time on arrival, with the planned gate time submitted by the airport or by Airport Coordination Ltd up to 30 minutes before operation. A flight is generally counted as on time if it departs anywhere from more than 15 minutes early up to 15 minutes late, which is a wider window than most passengers assume.
It is worth remembering that the CAA itself cautions against treating any single month as a verdict on an airport. Severe weather, air traffic control restrictions, strikes and one off technical issues can all skew a month’s figures without reflecting how that airport or airline performs over a full year.
A worked example: comparing the UK’s four busiest airports
To show how the CAA data behaves in practice, here is a snapshot from June, drawn from CAA punctuality tables published that year. Heathrow, Gatwick, Stansted and Manchester are consistently the UK’s four busiest airports by flight volume, so they make a useful like for like comparison. In this particular month, Stansted recorded the lowest cancellation rate of the four, with 81 cancellations from 14,171 scheduled departures, a rate of under 0.6 per cent. Heathrow recorded 637 cancellations from 33,793 departures, a rate of just under 2 per cent. Among the UK’s smaller regional airports that same month, Bournemouth, Exeter and Teesside International all reported zero cancelled flights.
On the early departures side, East Midlands Airport, Leeds Bradford and Exeter led the table, with 6.92 per cent, 5.83 per cent and 5.06 per cent of flights respectively departing more than 15 minutes ahead of schedule. Seven airports, including Belfast City, Belfast International, East Midlands, Exeter, Liverpool, Southampton and Teesside International, saw close to a third of their flights depart somewhere between 1 and 15 minutes early.
Because cancellation and punctuality rates shift from month to month, treat the table below as a snapshot rather than a current league table. For up to date figures, the CAA publishes a fresh monthly release, typically around the 16th of the following month, with full annual roundups each March.
| Airport | Number of flights | Flights more than 15 minutes early (%) | Flights 15 minutes early to 1 minute early (%) | Flights cancelled (%) |
|---|---|---|---|---|
| Aberdeen | 2127 | 4.1 | 30.6 | 2.7 |
| Belfast City (George Best) | 1339 | 9.9 | 37.7 | 1.5 |
| Belfast International | 2890 | 4.5 | 36.7 | 1.3 |
| Birmingham | 5354 | 4.6 | 20.6 | 0.5 |
| Bournemouth | 455 | 3.7 | 33.0 | 0.0 |
| Bristol | 4642 | 3.0 | 29.4 | 1.1 |
| Cardiff Wales | 458 | 1.9 | 31.8 | 0.9 |
| Doncaster Sheffield | 499 | 4.2 | 18.4 | 0.0 |
| East Midlands International | 1638 | 6.6 | 44.2 | 0.4 |
| Edinburgh | 7274 | 4.1 | 27.3 | 1.6 |
| Exeter | 518 | 5.4 | 38.6 | 0.0 |
| Gatwick | 18534 | 8.2 | 28.4 | 0.6 |
| Glasgow | 4616 | 4.9 | 37.3 | 2.0 |
| Heathrow | 31792 | 7.1 | 27.0 | 1.6 |
| Isle of Man | 670 | 6.4 | 38.7 | 2.2 |
| Jersey | 1284 | 4.1 | 30.9 | 1.2 |
| Leeds Bradford | 1890 | 7.9 | 29.9 | 0.3 |
| Liverpool (John Lennon) | 2306 | 3.4 | 39.6 | 0.9 |
| London City | 3867 | 8.3 | 32.9 | 2.4 |
| Luton | 7664 | 3.0 | 24.4 | 0.6 |
| Manchester | 12355 | 4.6 | 20.9 | 0.9 |
| Newcastle | 2504 | 5.6 | 24.8 | 0.6 |
| Southampton | 1233 | 2.9 | 29.2 | 4.4 |
| Stansted | 13024 | 2.1 | 31.0 | 0.8 |
| Teesside International | 370 | 7.6 | 43.5 | 0.0 |
The complete monthly tables, including every airport and route combination, are published in full by the CAA on its flight punctuality statistics page.
Common questions about UK airport delays and cancellations
Which UK airport has the lowest cancellation rate?
This changes monthly, but smaller regional airports such as Bournemouth, Exeter, Doncaster Sheffield and Teesside International frequently report zero or near zero cancellations, largely because they handle far fewer daily movements than London’s major hubs. Among the busiest UK airports, Stansted has a strong recent track record of comparatively low cancellation rates.
Why do flights depart early?
Early departures usually happen when an aircraft completes boarding ahead of its scheduled slot and air traffic control allows it to push back sooner, particularly during quieter periods or on routes with built in schedule padding. The CAA counts any departure more than 15 minutes ahead of schedule as an early flight, and at several UK airports this can apply to one in ten or more services in a given month.
What counts as an on time flight in the UK?
Under CAA methodology, a flight is treated as on time if it departs anywhere between more than 15 minutes early and 15 minutes late. This is a wider definition than the 15 minute late threshold often used informally, and it means published on time percentages can look higher than passengers might expect from their own experience.
Do bigger airports have more delays?
Not necessarily, but they do face more variables. Airports handling tens of thousands of monthly departures, such as Heathrow, Gatwick and Manchester, operate on tighter runway and stand capacity, so a single weather event, technical fault or air traffic control restriction has a larger knock on effect across the schedule. Smaller airports have less capacity pressure, which is part of why their cancellation rates often look lower, though their absolute flight numbers are also far smaller, so a handful of cancellations moves the percentage more sharply.
Where can I find this month’s UK airport punctuality data?
The CAA publishes a new monthly release, with full and summary tables in PDF, CSV and XLSX format, and an annual roundup each March. You can browse every month on the CAA’s UK flight punctuality statistics page.
Planning around delays: what you can control
Punctuality data is useful context, but most disruption risk comes down to factors specific to your route, airline and travel dates rather than the airport’s overall track record. A few practical steps make the biggest difference. Check your airline’s app for live gate and boarding updates rather than relying on airport screens alone, since airline apps usually update faster. Build in extra time during peak summer months and around school holidays, when both passenger volumes and weather related disruption tend to rise together. If you are driving to the airport, booking airport parking in advance avoids losing time to a sold out car park or an unexpectedly long walk from an overflow site, which matters more on the days when delays are already eating into your schedule.
Whichever UK airport you are flying from, from Birmingham and Bristol to Gatwick, Heathrow, Manchester and Stansted, APH compares official and trusted parking options so you can book a space, an airport hotel or airport lounge access ahead of your trip and focus on getting to your gate rather than worrying about the car park.
This is a sensitive topic for anyone with an upcoming flight, and the figures above describe industry wide averages for a single past month rather than a guarantee for any specific flight. Always check your airline’s own status updates closer to your travel date.