UK FLIGHT DELAY INDEX

derived from CAA punctuality statistics for UK reporting airports

How often are these flights late or cancelled?

Australia

In the twelve months from July 2025 to June 2026, 20.5% of 1,107 movements arriving into the UK were disrupted — more than fifteen minutes late or cancelled at short notice.

Put the other way round, 79.5% of 1,107 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

20.5% of 1,107 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
20.5% of 1,107 movements1.5% of 1,107 movements42.4–98.2 minutes; delayed denominator 210–4611.5% of 1,107 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?

1.5% of 1,107 movements passed the three-hour mark.

The ladder shows how many movements crossed each threshold. Cancellations are separate: 1.5% of 1,107 movements.

DelayShare and sampleOne event per movements
More than 15 minutes19.0% of 1,107 movements5.3
More than 30 minutes10.7% of 1,107 movements9.4
More than 60 minutes6.0% of 1,107 movements16.8
More than 120 minutes2.3% of 1,107 movements44.3
More than 180 minutes1.5% of 1,107 movements65.1
More than 360 minutes0.6% of 1,107 movements158.1
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?

2.3% of 1,107 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 early35331.9%15–1 early27624.9%0–15 late25122.7%16–30928.3%31–60524.7%61…120413.7%121…18080.7%181…360100.9%>36070.6%D=1,107
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: Jan 2022, 11.8% of 51 movements. Worst month: Apr 2023, 85.6% of 90 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: 25.8%; sample: 932018Feb 2018: 17.1%; sample: 82Mar 2018: 25.0%; sample: 92Apr 2018: 46.7%; sample: 90May 2018: 21.5%; sample: 93Jun 2018: 13.3%; sample: 90Jul 2018: 14.0%; sample: 93Aug 2018: 15.1%; sample: 93Sep 2018: 18.9%; sample: 90Oct 2018: 35.5%; sample: 93Nov 2018: 47.3%; sample: 91Dec 2018: 44.1%; sample: 93Jan 2019: 46.2%; sample: 932019Feb 2019: 50.0%; sample: 84Mar 2019: 71.0%; sample: 93Apr 2019: 73.3%; sample: 90May 2019: 56.4%; sample: 94Jun 2019: 42.2%; sample: 90Jul 2019: 27.7%; sample: 94Aug 2019: 28.7%; sample: 94Sep 2019: 36.7%; sample: 90Oct 2019: 37.6%; sample: 93Nov 2019: 34.4%; sample: 90Dec 2019: 33.3%; sample: 93Jan 2020: 57.0%; sample: 932020Feb 2020: 62.1%; sample: 87Mar 2020: 33.3%; sample: 87Apr 2020: suppressed: fewer than twenty movements×May 2020: suppressed: fewer than twenty movements×Jun 2020: suppressed: fewer than twenty movements×Jul 2020: suppressed: fewer than twenty movements×Aug 2020: suppressed: fewer than twenty movements×Sep 2020: suppressed: fewer than twenty movements×Oct 2020: suppressed: fewer than twenty movements×Nov 2020: suppressed: fewer than twenty movements×Dec 2020: suppressed: fewer than twenty movements×Jan 2021: suppressed: fewer than twenty movements×2021Feb 2021: suppressed: fewer than twenty movements×Mar 2021: suppressed: fewer than twenty movements×Apr 2021: suppressed: fewer than twenty movements×May 2021: suppressed: fewer than twenty movements×Jun 2021: suppressed: fewer than twenty movements×Jul 2021: suppressed: fewer than twenty movements×Aug 2021: suppressed: fewer than twenty movements×Sep 2021: suppressed: fewer than twenty movements×Oct 2021: suppressed: fewer than twenty movements×Nov 2021: suppressed: fewer than twenty movements×Dec 2021: 21.1%; sample: 38Jan 2022: 11.8%; sample: 512022Feb 2022: 19.0%; sample: 42Mar 2022: 38.7%; sample: 62Apr 2022: 54.4%; sample: 90May 2022: 36.6%; sample: 93Jun 2022: 43.3%; sample: 90Jul 2022: 51.6%; sample: 93Aug 2022: 45.7%; sample: 92Sep 2022: 49.5%; sample: 91Oct 2022: 70.1%; sample: 97Nov 2022: 43.3%; sample: 90Dec 2022: 70.2%; sample: 94Jan 2023: 45.2%; sample: 932023Feb 2023: 56.5%; sample: 85Mar 2023: 63.4%; sample: 93Apr 2023: 85.6%; sample: 90May 2023: 60.2%; sample: 93Jun 2023: 34.8%; sample: 89Jul 2023: 22.3%; sample: 94Aug 2023: 18.9%; sample: 95Sep 2023: 31.1%; sample: 90Oct 2023: 58.7%; sample: 92Nov 2023: 70.3%; sample: 91Dec 2023: 60.0%; sample: 95Jan 2024: 51.6%; sample: 932024Feb 2024: 52.9%; sample: 87Mar 2024: 42.6%; sample: 94Apr 2024: 54.7%; sample: 95May 2024: 35.5%; sample: 93Jun 2024: 22.2%; sample: 90Jul 2024: 14.0%; sample: 93Aug 2024: 20.2%; sample: 94Sep 2024: 25.3%; sample: 91Oct 2024: 31.5%; sample: 92Nov 2024: 14.3%; sample: 91Dec 2024: 22.6%; sample: 93Jan 2025: 23.7%; sample: 932025Feb 2025: 33.3%; sample: 84Mar 2025: 19.6%; sample: 92Apr 2025: 34.4%; sample: 90May 2025: 40.6%; sample: 96Jun 2025: 30.8%; sample: 91Jul 2025: 16.8%; sample: 95Aug 2025: 17.2%; sample: 93Sep 2025: 13.3%; sample: 90Oct 2025: 33.3%; sample: 93Nov 2025: 15.6%; sample: 90Dec 2025: 17.7%; sample: 96Jan 2026: 22.6%; sample: 932026Feb 2026: 19.0%; sample: 84Mar 2026: 15.3%; sample: 98Apr 2026: 27.5%; sample: 91May 2026: 26.6%; sample: 94Jun 2026: 21.1%; sample: 90Pandemic regime Jun 2020Summer 2022 breakdown Jul 2022NATS system failure Aug 2023Heathrow fire closure Mar 2025100%0%
Every monthly observation
MonthDisruption on arrivals
Jan 201825.8% of 93 movements
Feb 201817.1% of 82 movements
Mar 201825.0% of 92 movements
Apr 201846.7% of 90 movements
May 201821.5% of 93 movements
Jun 201813.3% of 90 movements
Jul 201814.0% of 93 movements
Aug 201815.1% of 93 movements
Sep 201818.9% of 90 movements
Oct 201835.5% of 93 movements
Nov 201847.3% of 91 movements
Dec 201844.1% of 93 movements
Jan 201946.2% of 93 movements
Feb 201950.0% of 84 movements
Mar 201971.0% of 93 movements
Apr 201973.3% of 90 movements
May 201956.4% of 94 movements
Jun 201942.2% of 90 movements
Jul 201927.7% of 94 movements
Aug 201928.7% of 94 movements
Sep 201936.7% of 90 movements
Oct 201937.6% of 93 movements
Nov 201934.4% of 90 movements
Dec 201933.3% of 93 movements
Jan 202057.0% of 93 movements
Feb 202062.1% of 87 movements
Mar 202033.3% of 87 movements
Apr 2020suppressed: fewer than twenty movements
May 2020suppressed: fewer than twenty movements
Jun 2020suppressed: fewer than twenty movements
Jul 2020suppressed: fewer than twenty movements
Aug 2020suppressed: fewer than twenty movements
Sep 2020suppressed: fewer than twenty movements
Oct 2020suppressed: fewer than twenty movements
Nov 2020suppressed: fewer than twenty movements
Dec 2020suppressed: fewer than twenty movements
Jan 2021suppressed: fewer than twenty movements
Feb 2021suppressed: fewer than twenty movements
Mar 2021suppressed: fewer than twenty movements
Apr 2021suppressed: fewer than twenty movements
May 2021suppressed: fewer than twenty movements
Jun 2021suppressed: fewer than twenty movements
Jul 2021suppressed: fewer than twenty movements
Aug 2021suppressed: fewer than twenty movements
Sep 2021suppressed: fewer than twenty movements
Oct 2021suppressed: fewer than twenty movements
Nov 2021suppressed: fewer than twenty movements
Dec 202121.1% of 38 movements — small sample, not ranked
Jan 202211.8% of 51 movements
Feb 202219.0% of 42 movements — small sample, not ranked
Mar 202238.7% of 62 movements
Apr 202254.4% of 90 movements
May 202236.6% of 93 movements
Jun 202243.3% of 90 movements
Jul 202251.6% of 93 movements
Aug 202245.7% of 92 movements
Sep 202249.5% of 91 movements
Oct 202270.1% of 97 movements
Nov 202243.3% of 90 movements
Dec 202270.2% of 94 movements
Jan 202345.2% of 93 movements
Feb 202356.5% of 85 movements
Mar 202363.4% of 93 movements
Apr 202385.6% of 90 movements
May 202360.2% of 93 movements
Jun 202334.8% of 89 movements
Jul 202322.3% of 94 movements
Aug 202318.9% of 95 movements
Sep 202331.1% of 90 movements
Oct 202358.7% of 92 movements
Nov 202370.3% of 91 movements
Dec 202360.0% of 95 movements
Jan 202451.6% of 93 movements
Feb 202452.9% of 87 movements
Mar 202442.6% of 94 movements
Apr 202454.7% of 95 movements
May 202435.5% of 93 movements
Jun 202422.2% of 90 movements
Jul 202414.0% of 93 movements
Aug 202420.2% of 94 movements
Sep 202425.3% of 91 movements
Oct 202431.5% of 92 movements
Nov 202414.3% of 91 movements
Dec 202422.6% of 93 movements
Jan 202523.7% of 93 movements
Feb 202533.3% of 84 movements
Mar 202519.6% of 92 movements
Apr 202534.4% of 90 movements
May 202540.6% of 96 movements
Jun 202530.8% of 91 movements
Jul 202516.8% of 95 movements
Aug 202517.2% of 93 movements
Sep 202513.3% of 90 movements
Oct 202533.3% of 93 movements
Nov 202515.6% of 90 movements
Dec 202517.7% of 96 movements
Jan 202622.6% of 93 movements
Feb 202619.0% of 84 movements
Mar 202615.3% of 98 movements
Apr 202627.5% of 91 movements
May 202626.6% of 94 movements
Jun 202621.1% of 90 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 2022Arrivals51.6% of 93 movementsno complete baselinenot enough data: needs a complete baseline and a publishable event month
Summer 2022 breakdown · Jul 2022Departures77.7% of 94 movementsno complete baselinenot enough data: needs a complete baseline and a publishable event month
NATS system failure · Aug 2023Arrivals18.9% of 95 movements53.9% across 1,101 flightsreturned the next month
NATS system failure · Aug 2023Departures40.0% of 95 movements46.4% across 1,101 flightsreturned after 2 months
Heathrow fire closure · Mar 2025Arrivals19.6% of 92 movements28.3% across 1,103 flightsreturned after 4 months
Heathrow fire closure · Mar 2025Departures16.0% of 94 movements33.7% across 1,099 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: Apr, 54.4% across 7 months. Lowest median: Aug, 19.6% 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.

Seasonality: calendar month by year; share and nJanFebMarAprMayJunJulAugSepOctNovDec201946.2% of 93 movements50.0% of 84 movements71.0% of 93 movements73.3% of 90 movements56.4% of 94 movements42.2% of 90 movements27.7% of 94 movements28.7% of 94 movements36.7% of 90 movements37.6% of 93 movements34.4% of 90 movements33.3% of 93 movements202057.0% of 93 movements62.1% of 87 movements33.3% of 87 movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movements2021suppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movementssuppressed: fewer than twenty movements21.1% of 38 movements †202211.8% of 51 movements19.0% of 42 movements †38.7% of 62 movements54.4% of 90 movements36.6% of 93 movements43.3% of 90 movements51.6% of 93 movements45.7% of 92 movements49.5% of 91 movements70.1% of 97 movements43.3% of 90 movements70.2% of 94 movements202345.2% of 93 movements56.5% of 85 movements63.4% of 93 movements85.6% of 90 movements60.2% of 93 movements34.8% of 89 movements22.3% of 94 movements18.9% of 95 movements31.1% of 90 movements58.7% of 92 movements70.3% of 91 movements60.0% of 95 movements202451.6% of 93 movements52.9% of 87 movements42.6% of 94 movements54.7% of 95 movements35.5% of 93 movements22.2% of 90 movements14.0% of 93 movements20.2% of 94 movements25.3% of 91 movements31.5% of 92 movements14.3% of 91 movements22.6% of 93 movements202523.7% of 93 movements33.3% of 84 movements19.6% of 92 movements34.4% of 90 movements40.6% of 96 movements30.8% of 91 movements16.8% of 95 movements17.2% of 93 movements13.3% of 90 movements33.3% of 93 movements15.6% of 90 movements17.7% of 96 movements202622.6% of 93 movements19.0% of 84 movements15.3% of 98 movements27.5% of 91 movements26.6% of 94 movements21.1% of 90 movementsno datano datano datano datano datano data
Month-by-month table: median, observed range and sample
MonthMedianObserved rangeSample
Jan25.8%11.8–51.6%7 months, 609 flights
Feb33.3%17.1–56.5%7 months, 548 flights
Mar38.7%15.3–71.0%7 months, 624 flights
Apr54.4%27.5–85.6%7 months, 636 flights
May36.6%21.5–60.2%7 months, 656 flights
Jun30.8%13.3–43.3%7 months, 630 flights
Jul19.6%14.0–51.6%6 months, 562 flights
Aug19.6%15.1–45.7%6 months, 561 flights
Sep28.2%13.3–49.5%6 months, 542 flights
Oct36.6%31.5–70.1%6 months, 560 flights
Nov38.9%14.3–70.3%6 months, 543 flights
Dec38.7%17.7–70.2%6 months, 564 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: LHR ↔ PERTH-AUSTRALIA, 13.4% of 367 movements. Highest disruption: LHR ↔ SYDNEY, 23.8% of 738 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 optionLhr ↔ Perth-Australia13.4% of 367 flightsLhr ↔ Sydney23.8% of 738 flights
All route comparisons and sample flags
RouteDisruptionCancellationsSample flag
LHR ↔ PERTH-AUSTRALIA13.4% of 367 movements0.8% of 367 movementsdescriptive comparison
Heathrow ↔ Sydney23.8% of 738 movements1.9% of 738 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?

1 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
Heathrow20.4% of 1,105 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

20.5% of 1,107 movements arrivals were disrupted, against 23.1% of 1,105 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

1.5% of 1,107 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

Australia appears from Jan 2018 to Jun 2026 with 7,409 arrivals.

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

Archive route pairs: 8.

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?

20.5% of 1,107 movements over July 2025 to June 2026.

How often are they cancelled?

1.5% of 1,107 movements at short notice.

How late is late?

42.4–98.2 minutes; delayed denominator 210–461

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.