UK FLIGHT DELAY INDEX

derived from CAA punctuality statistics for UK reporting airports

How often are these flights late or cancelled?

Air Portugal

In the twelve months from July 2025 to June 2026, 35.4% of 3,845 movements arriving into the UK were disrupted — more than fifteen minutes late or cancelled at short notice.

Put the other way round, 64.6% of 3,845 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

35.4% of 3,845 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.

DisruptionShort-notice cancellationsDelay among delayed movementsOver three hours
35.4% of 3,845 movements0.5% of 3,845 movements22.4–46.5 minutes; delayed denominator 1,340–2,6070.1% of 3,845 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?

0.1% of 3,845 movements passed the three-hour mark.

The ladder shows how many movements crossed each threshold. Cancellations are separate: 0.5% of 3,845 movements.

DelayShare and sampleOne event per movements
More than 15 minutes34.9% of 3,845 movements2.9
More than 30 minutes17.0% of 3,845 movements5.9
More than 60 minutes4.9% of 3,845 movements20.5
More than 120 minutes0.7% of 3,845 movements153.8
More than 180 minutes0.1% of 3,845 movements1,922.5
More than 360 minutesno events in 3,845 movementsNo observed events; this is not zero risk.
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?

0.7% of 3,845 movements passed two hours.

The histogram shows the published delay bands. Bucket shares use all reported operations, including unmatched records; cancellations are reported separately.

Nine delay buckets, minutes; share of all recorded operations>15 early2265.9%15–1 early99225.8%0–15 late1,26733.0%16–3068617.8%31–6046612.1%61…1201634.2%121…180230.6%181…36020.1%>36000.0%D=3,845
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: Sep 2020, 0.9% of 114 movements. Worst month: Sep 2024, 70.3% of 340 movements.

The line traces every month. Lower disruption is better; gaps are never zeros. Pandemic readings describe a different operating regime.

Monthly disruption share; gaps mean no published dataJan 2018: 29.1%; sample: 3812018Feb 2018: 33.5%; sample: 343Mar 2018: 39.1%; sample: 394Apr 2018: 43.4%; sample: 410May 2018: 42.9%; sample: 422Jun 2018: 49.4%; sample: 425Jul 2018: 40.7%; sample: 442Aug 2018: 43.1%; sample: 441Sep 2018: 44.3%; sample: 427Oct 2018: 45.8%; sample: 432Nov 2018: 28.7%; sample: 331Dec 2018: 31.8%; sample: 336Jan 2019: 24.8%; sample: 4002019Feb 2019: 17.3%; sample: 359Mar 2019: 20.6%; sample: 399Apr 2019: 34.9%; sample: 424May 2019: 34.6%; sample: 361Jun 2019: 30.4%; sample: 352Jul 2019: 45.2%; sample: 363Aug 2019: 46.7%; sample: 364Sep 2019: 54.8%; sample: 352Oct 2019: 32.9%; sample: 350Nov 2019: 22.4%; sample: 303Dec 2019: 38.0%; sample: 334Jan 2020: 32.1%; sample: 3242020Feb 2020: 31.5%; sample: 289Mar 2020: 15.4%; sample: 228Apr 2020: suppressed: fewer than twenty movements×May 2020: suppressed: fewer than twenty movements×Jun 2020: suppressed: fewer than twenty movements×Jul 2020: 3.2%; sample: 62Aug 2020: 2.8%; sample: 107Sep 2020: 0.9%; sample: 114Oct 2020: 2.2%; sample: 89Nov 2020: 1.1%; sample: 88Dec 2020: 3.4%; sample: 118Jan 2021: 9.2%; sample: 652021Feb 2021: suppressed: fewer than twenty movements×Mar 2021: suppressed: fewer than twenty movements×Apr 2021: 13.3%; sample: 30May 2021: 2.2%; sample: 92Jun 2021: 2.1%; sample: 191Jul 2021: 9.6%; sample: 177Aug 2021: 12.3%; sample: 179Sep 2021: 11.2%; sample: 152Oct 2021: 15.6%; sample: 179Nov 2021: 18.5%; sample: 302Dec 2021: 13.2%; sample: 304Jan 2022: 15.1%; sample: 2392022Feb 2022: 7.8%; sample: 244Mar 2022: 5.7%; sample: 298Apr 2022: 31.7%; sample: 334May 2022: 31.4%; sample: 357Jun 2022: 40.3%; sample: 357Jul 2022: 47.6%; sample: 368Aug 2022: 40.1%; sample: 369Sep 2022: 59.4%; sample: 355Oct 2022: 46.8%; sample: 365Nov 2022: 26.2%; sample: 282Dec 2022: 36.5%; sample: 307Jan 2023: 30.0%; sample: 3132023Feb 2023: 31.1%; sample: 280Mar 2023: 43.0%; sample: 321Apr 2023: 44.5%; sample: 346May 2023: 42.6%; sample: 359Jun 2023: 43.4%; sample: 350Jul 2023: 41.9%; sample: 377Aug 2023: 45.0%; sample: 373Sep 2023: 48.6%; sample: 364Oct 2023: 48.1%; sample: 366Nov 2023: 33.9%; sample: 298Dec 2023: 35.5%; sample: 307Jan 2024: 19.8%; sample: 2982024Feb 2024: 23.1%; sample: 273Mar 2024: 34.8%; sample: 305Apr 2024: 43.4%; sample: 343May 2024: 43.6%; sample: 351Jun 2024: 39.1%; sample: 338Jul 2024: 42.9%; sample: 345Aug 2024: 45.1%; sample: 344Sep 2024: 70.3%; sample: 340Oct 2024: 59.3%; sample: 329Nov 2024: 31.8%; sample: 289Dec 2024: 37.6%; sample: 298Jan 2025: 35.7%; sample: 3082025Feb 2025: 33.0%; sample: 270Mar 2025: 40.8%; sample: 306Apr 2025: 44.5%; sample: 337May 2025: 37.0%; sample: 346Jun 2025: 34.6%; sample: 338Jul 2025: 53.4%; sample: 354Aug 2025: 44.6%; sample: 352Sep 2025: 48.2%; sample: 336Oct 2025: 42.7%; sample: 337Nov 2025: 34.5%; sample: 293Dec 2025: 28.3%; sample: 290Jan 2026: 27.5%; sample: 3052026Feb 2026: 25.7%; sample: 276Mar 2026: 27.6%; sample: 304Apr 2026: 23.8%; sample: 336May 2026: 30.0%; sample: 343Jun 2026: 32.3%; sample: 319Pandemic regime Jun 2020Summer 2022 breakdown Jul 2022NATS system failure Aug 2023Heathrow fire closure Mar 2025100%0%
Every monthly observation
MonthDisruption on arrivals
Jan 201829.1% of 381 movements
Feb 201833.5% of 343 movements
Mar 201839.1% of 394 movements
Apr 201843.4% of 410 movements
May 201842.9% of 422 movements
Jun 201849.4% of 425 movements
Jul 201840.7% of 442 movements
Aug 201843.1% of 441 movements
Sep 201844.3% of 427 movements
Oct 201845.8% of 432 movements
Nov 201828.7% of 331 movements
Dec 201831.8% of 336 movements
Jan 201924.8% of 400 movements
Feb 201917.3% of 359 movements
Mar 201920.6% of 399 movements
Apr 201934.9% of 424 movements
May 201934.6% of 361 movements
Jun 201930.4% of 352 movements
Jul 201945.2% of 363 movements
Aug 201946.7% of 364 movements
Sep 201954.8% of 352 movements
Oct 201932.9% of 350 movements
Nov 201922.4% of 303 movements
Dec 201938.0% of 334 movements
Jan 202032.1% of 324 movements
Feb 202031.5% of 289 movements
Mar 202015.4% of 228 movements
Apr 2020suppressed: fewer than twenty movements
May 2020suppressed: fewer than twenty movements
Jun 2020suppressed: fewer than twenty movements
Jul 20203.2% of 62 movements
Aug 20202.8% of 107 movements
Sep 20200.9% of 114 movements
Oct 20202.2% of 89 movements
Nov 20201.1% of 88 movements
Dec 20203.4% of 118 movements
Jan 20219.2% of 65 movements
Feb 2021suppressed: fewer than twenty movements
Mar 2021suppressed: fewer than twenty movements
Apr 202113.3% of 30 movements — small sample, not ranked
May 20212.2% of 92 movements
Jun 20212.1% of 191 movements
Jul 20219.6% of 177 movements
Aug 202112.3% of 179 movements
Sep 202111.2% of 152 movements
Oct 202115.6% of 179 movements
Nov 202118.5% of 302 movements
Dec 202113.2% of 304 movements
Jan 202215.1% of 239 movements
Feb 20227.8% of 244 movements
Mar 20225.7% of 298 movements
Apr 202231.7% of 334 movements
May 202231.4% of 357 movements
Jun 202240.3% of 357 movements
Jul 202247.6% of 368 movements
Aug 202240.1% of 369 movements
Sep 202259.4% of 355 movements
Oct 202246.8% of 365 movements
Nov 202226.2% of 282 movements
Dec 202236.5% of 307 movements
Jan 202330.0% of 313 movements
Feb 202331.1% of 280 movements
Mar 202343.0% of 321 movements
Apr 202344.5% of 346 movements
May 202342.6% of 359 movements
Jun 202343.4% of 350 movements
Jul 202341.9% of 377 movements
Aug 202345.0% of 373 movements
Sep 202348.6% of 364 movements
Oct 202348.1% of 366 movements
Nov 202333.9% of 298 movements
Dec 202335.5% of 307 movements
Jan 202419.8% of 298 movements
Feb 202423.1% of 273 movements
Mar 202434.8% of 305 movements
Apr 202443.4% of 343 movements
May 202443.6% of 351 movements
Jun 202439.1% of 338 movements
Jul 202442.9% of 345 movements
Aug 202445.1% of 344 movements
Sep 202470.3% of 340 movements
Oct 202459.3% of 329 movements
Nov 202431.8% of 289 movements
Dec 202437.6% of 298 movements
Jan 202535.7% of 308 movements
Feb 202533.0% of 270 movements
Mar 202540.8% of 306 movements
Apr 202544.5% of 337 movements
May 202537.0% of 346 movements
Jun 202534.6% of 338 movements
Jul 202553.4% of 354 movements
Aug 202544.6% of 352 movements
Sep 202548.2% of 336 movements
Oct 202542.7% of 337 movements
Nov 202534.5% of 293 movements
Dec 202528.3% of 290 movements
Jan 202627.5% of 305 movements
Feb 202625.7% of 276 movements
Mar 202627.6% of 304 movements
Apr 202623.8% of 336 movements
May 202630.0% of 343 movements
Jun 202632.3% of 319 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.

EventDirectionDisruption that monthBaseline beforeReturn to baseline
Pandemic regime · Jun 2020Arrivalssuppressed: fewer than twenty movementsno complete baselinenot enough data: needs a complete baseline and a publishable event month
Pandemic regime · Jun 2020Departuressuppressed: fewer than twenty movementsno complete baselinenot enough data: needs a complete baseline and a publishable event month
Summer 2022 breakdown · Jul 2022Arrivals47.6% of 368 movements17.7% across 3,122 flightsstill above it 8 months later
Summer 2022 breakdown · Jul 2022Departures65.0% of 366 movements21.7% across 3,125 flightsstill above it 8 months later
NATS system failure · Aug 2023Arrivals45.0% of 373 movements40.5% across 4,024 flightsreturned after 3 months
NATS system failure · Aug 2023Departures50.9% of 373 movements49.0% across 4,023 flightsreturned after 2 months
Heathrow fire closure · Mar 2025Arrivals40.8% of 306 movements43.0% across 3,860 flightsreturned after 2 months
Heathrow fire closure · Mar 2025Departures51.1% of 309 movements51.5% across 3,871 flightsreturned 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, 51.7% across 6 months. Lowest median: Feb, 25.7% across 7 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.

Seasonality: calendar month by year; share and nJanFebMarAprMayJunJulAugSepOctNovDec201924.8% of 400 movements17.3% of 359 movements20.6% of 399 movements34.9% of 424 movements34.6% of 361 movements30.4% of 352 movements45.2% of 363 movements46.7% of 364 movements54.8% of 352 movements32.9% of 350 movements22.4% of 303 movements38.0% of 334 movements202032.1% of 324 movements31.5% of 289 movements15.4% of 228 movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movements3.2% of 62 movements2.8% of 107 movements0.9% of 114 movements2.2% of 89 movements1.1% of 88 movements3.4% of 118 movements20219.2% of 65 movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movements13.3% of 30 movements †2.2% of 92 movements2.1% of 191 movements9.6% of 177 movements12.3% of 179 movements11.2% of 152 movements15.6% of 179 movements18.5% of 302 movements13.2% of 304 movements202215.1% of 239 movements7.8% of 244 movements5.7% of 298 movements31.7% of 334 movements31.4% of 357 movements40.3% of 357 movements47.6% of 368 movements40.1% of 369 movements59.4% of 355 movements46.8% of 365 movements26.2% of 282 movements36.5% of 307 movements202330.0% of 313 movements31.1% of 280 movements43.0% of 321 movements44.5% of 346 movements42.6% of 359 movements43.4% of 350 movements41.9% of 377 movements45.0% of 373 movements48.6% of 364 movements48.1% of 366 movements33.9% of 298 movements35.5% of 307 movements202419.8% of 298 movements23.1% of 273 movements34.8% of 305 movements43.4% of 343 movements43.6% of 351 movements39.1% of 338 movements42.9% of 345 movements45.1% of 344 movements70.3% of 340 movements59.3% of 329 movements31.8% of 289 movements37.6% of 298 movements202535.7% of 308 movements33.0% of 270 movements40.8% of 306 movements44.5% of 337 movements37.0% of 346 movements34.6% of 338 movements53.4% of 354 movements44.6% of 352 movements48.2% of 336 movements42.7% of 337 movements34.5% of 293 movements28.3% of 290 movements202627.5% of 305 movements25.7% of 276 movements27.6% of 304 movements23.8% of 336 movements30.0% of 343 movements32.3% of 319 movementsno datano datano datano datano datano data
Month-by-month table: median, observed range and sample
MonthMedianObserved rangeSample
Jan27.5%15.1–35.7%7 months, 2,244 flights
Feb25.7%7.8–33.5%7 months, 2,045 flights
Mar34.8%5.7–43.0%7 months, 2,327 flights
Apr43.4%23.8–44.5%7 months, 2,530 flights
May37.0%30.0–43.6%7 months, 2,539 flights
Jun39.1%30.4–49.4%7 months, 2,479 flights
Jul44.0%40.7–53.4%6 months, 2,249 flights
Aug44.8%40.1–46.7%6 months, 2,243 flights
Sep51.7%44.3–70.3%6 months, 2,174 flights
Oct46.3%32.9–59.3%6 months, 2,179 flights
Nov30.3%22.4–34.5%6 months, 1,796 flights
Dec36.0%28.3–38.0%6 months, 1,872 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: LGW ↔ OPORTO-PORTUGAL, 25.5% of 619 movements. Highest disruption: MAN ↔ LISBON, 43.5% of 483 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.

Observed disruption share by optionLgw ↔ Oporto-Portugal25.5% of 619 flightsLgw ↔ Lisbon28.7% of 588 flightsLhr ↔ Lisbon38.2% of 2,152 flightsMan ↔ Lisbon43.5% of 483 flights
All route comparisons and sample flags
RouteDisruptionCancellationsSample flag
Gatwick ↔ Oporto (Portugal)25.5% of 619 movements0.5% of 619 movementsdescriptive comparison
Gatwick ↔ Lisbon28.7% of 588 movements0.9% of 588 movementsdescriptive comparison
Heathrow ↔ Lisbon38.2% of 2,152 movements0.4% of 2,152 movementsdescriptive comparison
Manchester ↔ Lisbon43.5% of 483 movements0.8% of 483 movementsdescriptive comparison
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?

3 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 airportDisruptionSample flag
Gatwick27.1% of 1,207 movementsdescriptive comparison
Heathrow38.2% of 2,152 movementsdescriptive comparison
Manchester43.5% of 483 movementsdescriptive comparison
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

35.4% of 3,845 movements arrivals were disrupted, against 40.1% of 3,842 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

0.1% of 3,845 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

Air Portugal appears from Jan 2018 to Jun 2026 with 29,784 arrivals.

The bounds describe the published record, not every commercial service. Final point is not necessarily a nonstop destination.

Archive route pairs: 21.

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?

35.4% of 3,845 movements over July 2025 to June 2026.

How often are they cancelled?

0.5% of 3,845 movements at short notice.

How late is late?

22.4–46.5 minutes; delayed denominator 1,340–2,607

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 complain
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.