How often are these flights late or cancelled?
KLM
In the twelve months from July 2025 to June 2026, 25.9% of 17,663 movements arriving into the UK were disrupted — more than fifteen minutes late or cancelled at short notice.
Put the other way round, 74.1% of 17,663 movements met the fifteen-minute convention. These are historical observations, not a forecast.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Source: CAA punctuality statistics · snapshot 17/08/2026 10:24 · method route-record-v2.1 · Versioned claims, formulas and entity mapping.
0 operations (0.00%) excluded because their published percentages could not be reconciled to whole numbers. Excluded operations enter neither the numerator nor the denominator. Outcome figures and comparisons are unavailable when the excluded share exceeds fifteen percent.
The four numbers at a glance
25.9% of 17,663 movements were disrupted over July 2025 to June 2026.
Average delay covers delayed movements only. Its range reflects rounded source means and the unknown count of exactly punctual movements.
| Disruption | Short-notice cancellations | Delay among delayed movements | Over three hours |
|---|---|---|---|
| 25.9% of 17,663 movements | 3.5% of 17,663 movements | 20.1–55.3 minutes; delayed denominator 3,954–10,035 | 0.3% of 17,663 movements |
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
When late, how late?
0.3% of 17,663 movements passed the three-hour mark.
The ladder shows how many movements crossed each threshold. Cancellations are separate: 3.5% of 17,663 movements.
| Delay | Share and sample | One event per movements |
|---|---|---|
| More than 15 minutes | 22.4% of 17,663 movements | 4.5 |
| More than 30 minutes | 12.1% of 17,663 movements | 8.3 |
| More than 60 minutes | 4.2% of 17,663 movements | 24.1 |
| More than 120 minutes | 0.8% of 17,663 movements | 119.3 |
| More than 180 minutes | 0.3% of 17,663 movements | 384.0 |
| More than 360 minutes | 0.0% of 17,663 movements | 5,887.7 |
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Slightly late or occasionally a disaster?
0.8% of 17,663 movements passed two hours.
The histogram shows the published delay bands. Bucket shares use all reported operations, including unmatched records; cancellations are reported separately.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Better or worse since the start of the archive?
Best month: Aug 2020, 0.9% of 657 movements. Worst month: Sep 2025, 44.1% of 1,501 movements.
The line traces every month. Lower disruption is better; gaps are never zeros. Pandemic readings describe a different operating regime.
Every monthly observation
| Month | Disruption on arrivals |
|---|---|
| Jan 2018 | 19.4% of 1,543 movements |
| Feb 2018 | 15.7% of 1,427 movements |
| Mar 2018 | 19.8% of 1,644 movements |
| Apr 2018 | 14.5% of 1,644 movements |
| May 2018 | 15.7% of 1,708 movements |
| Jun 2018 | 23.2% of 1,649 movements |
| Jul 2018 | 11.5% of 1,666 movements |
| Aug 2018 | 12.8% of 1,653 movements |
| Sep 2018 | 18.7% of 1,520 movements |
| Oct 2018 | 11.5% of 1,617 movements |
| Nov 2018 | 12.5% of 1,249 movements |
| Dec 2018 | 18.2% of 1,348 movements |
| Jan 2019 | 15.5% of 1,546 movements |
| Feb 2019 | 13.3% of 1,401 movements |
| Mar 2019 | 29.5% of 1,642 movements |
| Apr 2019 | 21.1% of 1,612 movements |
| May 2019 | 31.0% of 1,467 movements |
| Jun 2019 | 29.3% of 1,410 movements |
| Jul 2019 | 19.8% of 1,470 movements |
| Aug 2019 | 13.2% of 1,456 movements |
| Sep 2019 | 32.4% of 1,412 movements |
| Oct 2019 | 26.9% of 1,444 movements |
| Nov 2019 | 8.9% of 1,332 movements |
| Dec 2019 | 14.4% of 1,360 movements |
| Jan 2020 | 9.4% of 1,614 movements |
| Feb 2020 | 23.1% of 1,465 movements |
| Mar 2020 | 13.6% of 1,135 movements |
| Apr 2020 | 13.6% of 103 movements |
| May 2020 | 4.1% of 121 movements |
| Jun 2020 | 3.6% of 169 movements |
| Jul 2020 | 2.7% of 369 movements |
| Aug 2020 | 0.9% of 657 movements |
| Sep 2020 | 2.8% of 815 movements |
| Oct 2020 | 1.8% of 623 movements |
| Nov 2020 | 3.8% of 420 movements |
| Dec 2020 | 5.8% of 469 movements |
| Jan 2021 | 21.5% of 414 movements |
| Feb 2021 | suppressed: fewer than twenty movements |
| Mar 2021 | 34.6% of 104 movements |
| Apr 2021 | 18.8% of 325 movements |
| May 2021 | 3.5% of 431 movements |
| Jun 2021 | 7.5% of 518 movements |
| Jul 2021 | 5.6% of 737 movements |
| Aug 2021 | 17.2% of 749 movements |
| Sep 2021 | 19.5% of 768 movements |
| Oct 2021 | 18.7% of 818 movements |
| Nov 2021 | 7.1% of 902 movements |
| Dec 2021 | 15.3% of 1,023 movements |
| Jan 2022 | 18.3% of 969 movements |
| Feb 2022 | 23.9% of 782 movements |
| Mar 2022 | 11.5% of 995 movements |
| Apr 2022 | 36.4% of 1,189 movements |
| May 2022 | 36.9% of 1,373 movements |
| Jun 2022 | 43.8% of 1,378 movements |
| Jul 2022 | 31.8% of 1,187 movements |
| Aug 2022 | 20.6% of 1,136 movements |
| Sep 2022 | 41.4% of 1,175 movements |
| Oct 2022 | 19.5% of 1,133 movements |
| Nov 2022 | 7.8% of 1,104 movements |
| Dec 2022 | 21.2% of 1,099 movements |
| Jan 2023 | 11.4% of 1,135 movements |
| Feb 2023 | 10.5% of 1,079 movements |
| Mar 2023 | 23.5% of 1,279 movements |
| Apr 2023 | 19.8% of 1,322 movements |
| May 2023 | 24.7% of 1,430 movements |
| Jun 2023 | 27.2% of 1,406 movements |
| Jul 2023 | 27.1% of 1,512 movements |
| Aug 2023 | 23.7% of 1,501 movements |
| Sep 2023 | 31.3% of 1,432 movements |
| Oct 2023 | 36.2% of 1,549 movements |
| Nov 2023 | 30.6% of 1,559 movements |
| Dec 2023 | 39.8% of 1,601 movements |
| Jan 2024 | 30.8% of 1,499 movements |
| Feb 2024 | 24.7% of 1,449 movements |
| Mar 2024 | 21.5% of 1,622 movements |
| Apr 2024 | 33.2% of 1,471 movements |
| May 2024 | 22.2% of 1,522 movements |
| Jun 2024 | 26.6% of 1,458 movements |
| Jul 2024 | 26.8% of 1,498 movements |
| Aug 2024 | 20.6% of 1,513 movements |
| Sep 2024 | 34.0% of 1,504 movements |
| Oct 2024 | 23.5% of 1,587 movements |
| Nov 2024 | 24.5% of 1,528 movements |
| Dec 2024 | 28.2% of 1,571 movements |
| Jan 2025 | 34.6% of 1,516 movements |
| Feb 2025 | 19.2% of 1,379 movements |
| Mar 2025 | 18.2% of 1,581 movements |
| Apr 2025 | 18.2% of 1,531 movements |
| May 2025 | 22.7% of 1,554 movements |
| Jun 2025 | 26.6% of 1,470 movements |
| Jul 2025 | 36.1% of 1,481 movements |
| Aug 2025 | 29.9% of 1,480 movements |
| Sep 2025 | 44.1% of 1,501 movements |
| Oct 2025 | 32.5% of 1,580 movements |
| Nov 2025 | 19.5% of 1,550 movements |
| Dec 2025 | 20.6% of 1,575 movements |
| Jan 2026 | 38.7% of 1,345 movements |
| Feb 2026 | 16.1% of 1,227 movements |
| Mar 2026 | 13.8% of 1,585 movements |
| Apr 2026 | 15.8% of 1,448 movements |
| May 2026 | 16.6% of 1,466 movements |
| Jun 2026 | 26.9% of 1,425 movements |
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
What did the big disruptions do here?
Each event is compared with the twelve preceding calendar months and the first later return to baseline.
A worse month is not proof the named event caused it. The open data carry no delay-cause field. Recovery is observed for at most eight subsequent months.
| Event | Direction | Disruption that month | Baseline before | Return to baseline |
|---|---|---|---|---|
| Pandemic regime · Jun 2020 | Arrivals | 3.6% of 169 movements | 17.4% across 14,322 flights | returned the next month |
| Pandemic regime · Jun 2020 | Departures | 3.0% of 169 movements | 21.1% across 14,340 flights | returned the next month |
| Summer 2022 breakdown · Jul 2022 | Arrivals | 31.8% of 1,187 movements | 21.2% across 11,683 flights | returned the next month |
| Summer 2022 breakdown · Jul 2022 | Departures | 53.4% of 1,188 movements | 29.0% across 11,683 flights | returned after 3 months |
| NATS system failure · Aug 2023 | Arrivals | 23.7% of 1,501 movements | 21.2% across 14,810 flights | still above it 8 months later |
| NATS system failure · Aug 2023 | Departures | 32.8% of 1,504 movements | 29.8% across 14,812 flights | returned after 6 months |
| Heathrow fire closure · Mar 2025 | Arrivals | 18.2% of 1,581 movements | 26.2% across 18,169 flights | returned the next month |
| Heathrow fire closure · Mar 2025 | Departures | 25.1% of 1,579 movements | 35.3% across 18,167 flights | returned the next month |
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Which time of year has been hardest?
Highest median: Sep, 33.2% across 6 months. Lowest median: Nov, 16.0% across 6 months.
Even the same calendar month differs across years. This is a record, not a forecast; pandemic years are excluded from the summaries.
Each cell is one calendar month of one year; the number is the share of that month’s arrivals that were disrupted. Darker means worse. A blank cell means no published data, not zero.
Month-by-month table: median, observed range and sample
| Month | Median | Observed range | Sample |
|---|---|---|---|
| Jan | 19.4% | 11.4–38.7% | 7 months, 9,553 flights |
| Feb | 16.1% | 10.5–24.7% | 7 months, 8,744 flights |
| Mar | 19.8% | 11.5–29.5% | 7 months, 10,348 flights |
| Apr | 19.8% | 14.5–36.4% | 7 months, 10,217 flights |
| May | 22.7% | 15.7–36.9% | 7 months, 10,520 flights |
| Jun | 26.9% | 23.2–43.8% | 7 months, 10,196 flights |
| Jul | 26.9% | 11.5–36.1% | 6 months, 8,814 flights |
| Aug | 20.6% | 12.8–29.9% | 6 months, 8,739 flights |
| Sep | 33.2% | 18.7–44.1% | 6 months, 8,544 flights |
| Oct | 25.2% | 11.5–36.2% | 6 months, 8,910 flights |
| Nov | 16.0% | 7.8–30.6% | 6 months, 8,322 flights |
| Dec | 20.9% | 14.4–39.8% | 6 months, 8,554 flights |
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Which routes have the best and worst record?
Lowest disruption: LCY ↔ AMS, 15.1% of 2,194 movements. Highest disruption: ABZ ↔ AMS, 32.9% of 368 movements.
The airline table uses this carrier on each route; airport and country tables combine carriers. Each figure is arrivals into its UK airport. Only sufficiently large exact samples enter the ordered comparison.
All route comparisons and sample flags
| Route | Disruption | Cancellations | Sample flag |
|---|---|---|---|
| London City ↔ Amsterdam | 15.1% of 2,194 movements | 3.5% of 2,194 movements | descriptive comparison |
| EXT ↔ AMS | 18.5% of 356 movements | 4.2% of 356 movements | descriptive comparison |
| Cardiff Wales ↔ Amsterdam | 22.1% of 728 movements | 4.1% of 728 movements | descriptive comparison |
| Teesside International Airport ↔ Amsterdam | 23.0% of 846 movements | 4.3% of 846 movements | descriptive comparison |
| Leeds Bradford ↔ Amsterdam | 24.3% of 1,129 movements | 3.5% of 1,129 movements | descriptive comparison |
| Edinburgh ↔ Amsterdam | 24.8% of 1,580 movements | 2.7% of 1,580 movements | descriptive comparison |
| Heathrow ↔ Amsterdam | 26.6% of 2,764 movements | 3.3% of 2,764 movements | descriptive comparison |
| Glasgow ↔ Amsterdam | 27.5% of 926 movements | 3.0% of 926 movements | descriptive comparison |
| Birmingham ↔ Amsterdam | 27.7% of 1,685 movements | 3.1% of 1,685 movements | descriptive comparison |
| Newcastle ↔ Amsterdam | 29.5% of 1,633 movements | 1.5% of 1,633 movements | descriptive comparison |
| Manchester ↔ Amsterdam | 30.5% of 2,059 movements | 2.5% of 2,059 movements | descriptive comparison |
| Bristol ↔ Amsterdam | 31.9% of 1,349 movements | 2.6% of 1,349 movements | descriptive comparison |
| Aberdeen ↔ Amsterdam | 32.9% of 368 movements | 19.6% of 368 movements | descriptive comparison |
| Southampton ↔ Amsterdam | 100.0% of 22 movements — small sample, not ranked | 100.0% of 22 movements — small sample, not ranked | small sample; not ranked |
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Which UK airports appear in this record?
14 published groups have enough arrivals to describe.
These operations are not matched for season, aircraft or time of day. The table makes no causal comparison.
| UK airport | Disruption | Sample flag |
|---|---|---|
| Aberdeen | 32.9% of 368 movements | descriptive comparison |
| Birmingham | 27.7% of 1,685 movements | descriptive comparison |
| Bristol | 32.0% of 1,350 movements | descriptive comparison |
| Cardiff Wales | 22.2% of 729 movements | descriptive comparison |
| Edinburgh | 24.8% of 1,580 movements | descriptive comparison |
| Exeter | 18.5% of 356 movements | descriptive comparison |
| Glasgow | 27.5% of 926 movements | descriptive comparison |
| Leeds Bradford | 24.3% of 1,129 movements | descriptive comparison |
| London City | 15.1% of 2,194 movements | descriptive comparison |
| Heathrow | 26.6% of 2,765 movements | descriptive comparison |
| Manchester | 30.5% of 2,059 movements | descriptive comparison |
| Teesside International Airport | 23.0% of 846 movements | descriptive comparison |
| Newcastle | 29.6% of 1,634 movements | descriptive comparison |
| Southampton | 100.0% of 22 movements — small sample, not ranked | small sample; not ranked |
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Arrivals vs departures
25.9% of 17,663 movements arrivals were disrupted, against 33.9% of 17,669 movements departures.
The directions have separate denominators. A departure delay does not establish late arrival at the final destination; legal conditions differ by direction and carrier.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Movements past the three-hour mark
0.3% of 17,663 movements were more than three hours late over July 2025 to June 2026.
Cancellation is counted separately and is not a three-hour delay. Monthly counts cannot establish a passenger claim.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Facts about this record
KLM appears from Jan 2018 to Jun 2026 with 126,212 arrivals.
The bounds describe the published record, not every commercial service. Final point is not necessarily a nonstop destination.
Archive route pairs: 58.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
What this data cannot tell you
Delay cause, individual passenger experience, commercial decisions and future performance are not established here.
Also absent are aircraft type, within-month time-of-day splits and cancellations made ahead of the short-notice reporting window.
0 operations (0.00%) excluded because their published percentages could not be reconciled to whole numbers. Excluded operations enter neither the numerator nor the denominator. Outcome figures and comparisons are unavailable when the excluded share exceeds fifteen percent.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Quick answers
These answers use the same populations and window as the tables above.
Every percentage retains its denominator.
How disrupted are these arrivals?
25.9% of 17,663 movements over July 2025 to June 2026.
How often are they cancelled?
3.5% of 17,663 movements at short notice.
How late is late?
20.1–55.3 minutes; delayed denominator 3,954–10,035
Are services improving?
The monthly line records past changes; it is not a forecast or a causal comparison.
Which routes are compared?
The route table uses separately identified UK airport and final-point pairs, with small samples flagged.
Does this cover my flight?
Only published aggregate movements; the circumstances of any individual flight are unknown.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
How this was calculated
Source: CAA punctuality statistics · snapshot 17/08/2026 10:24 · method route-record-v2.1 · Versioned claims, formulas and entity mapping.
Integer bucket counts are recovered from rounding intervals over D=M+C+U with their sum constrained to M. Ambiguous counts remain ranges; failed reconciliation is quarantined.
Definitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.
Your trip has already gone wrong
The monthly line and events table show whether your month was typical or unusual in the published record.
Nothing here decides an individual case or what a passenger may be owed.
CAA: the official route to complainDefinitions, denominators and limits
Arrivals into UK reporting airports only unless labelled departures. Denominator: operated movements plus short-notice cancellations (M+C). A movement is not a scheduled flight. Unmatched records are data quality, not outcomes. Cells below twenty movements are suppressed; twenty to forty-nine are descriptive and not ranked.