Transatlantic route record · UK CAA departure punctuality
LHR→MIA
London to Miami
- Flights
- 3,819 both ways
- Carriers
- 3
- Distance
- 4,417 mi
- Period
- September 2025 to August 2026
Over the twelve months to August 2026, 73.9% of departures from London Heathrow to Miami International left within 15 minutes of their planned time, from 1,878 flights the UK Civil Aviation Authority matched to a schedule. That is 3 points behind the 76.4% recorded across every UK departure to the United States, and it ranks 28th of the 50 UK-to-US routes with a usable record. About one flight in four left at least 15 minutes behind schedule, and 36 of 1,914 scheduled departures, 1.9%, did not operate at all.
The route's 73.9% is essentially unchanged from the same twelve months a year earlier, when 73.6% left on time. Across every departure from the 25 UK airports the CAA reports, to any destination, 72.4% left within 15 minutes in the same period; transatlantic departures run slightly better than the UK average, partly because wide-body long-haul flights are scheduled with more slack than short-haul rotations. Within the route, the spread between carriers is 19 points, which matters more to a booking than the route average does.
Key figures
Left on time
73.9%
Within 15 minutes of schedule, of 1,878 departures (CAA)
Avg delay
15 min
Across all departures, early counted as zero
Cancelled
1.88%
All UK-to-US departures: 2.16%
3+ hours late
0.69%
The UK261 compensation threshold
5.3% of departures left more than an hour late, and 0.69% left three hours or more behind schedule, roughly one flight in 100. Three hours at arrival is the threshold at which UK261 compensation becomes payable, £520 a passenger on a sector of this length; the CAA measures the departure, so a flight in that band left the gate three hours late, which is not quite the same test but rarely ends differently after seven hours over the Atlantic. The average delay across every matched departure, early ones counted as zero, was 14.9 minutes, against 14.2 for all UK-to-US departures.
Carrier by carrier
Which airline leaves LHR for MIA on time
American Airlines is the most punctual carrier on the departing leg at 82.4% across 543 flights, and British Airways the least at 63.1% across 660. 19 points between them is a large gap for one city pair, large enough to prefer the better carrier at a modest fare difference. No carrier here cancels unusually often; the highest cancellation rate on the route is Virgin Atlantic's 2.8%.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| American Airlines | 550 | 82.4% | 11 min | 1.27% | B |
| Virgin Atlantic | 692 | 77.6% | 11 min | 2.75% | B |
| British Airways | 670 | 63.1% | 22 min | 1.49% | D |
Flights are scheduled departures in the CAA file, operated plus cancelled; on time is within 15 minutes of the planned off-block time. The DOT count below includes the return direction and may differ.
How late is late
How delays on LHR to MIA are distributed
- Early15+ min early0.1%
- On timeup to 15 min late73.8%
- 16–30 min11.1%
- 31–60 min8.0%
- 1–2 hours3.4%
- 2–3 hours1.2%
- 3–6 hourscompensation threshold0.6%
- Over 6 hours0.1%
Scale runs 0% to 100%.
Across the year
When LHR to MIA runs late
July was the weakest month for departures at 65.3% on time and February the strongest at 84.5%, a swing of 19 points across the year. That is a wide seasonal range, wider than the gap between the best and worst carriers, so the month you fly matters more than the airline you pick. The DOT's count puts the busiest month at 352 flights in April 2026 and the thinnest at 273 in June 2026, so capacity follows the summer peak.
Flights per month, both directions
- July 2025306
- August 2025307
- September 2025295
- October 2025313
- November 2025314
- December 2025331
- January 2026313
- February 2026330
- March 2026338
- April 2026352
- May 2026347
- June 2026273
The DOT's international report counts flights in both directions together: 3,819 between LHR and MIA from July 2025 to June 2026, about five departures a day in each direction, carrying 1,055,916 passengers. That makes it the 8th busiest of 31 US routes from London Heathrow and the busiest of 18 European routes into MIA.
The return leg
MIA to LHR: arrivals back into London
Coming the other way, 79.9% of arrivals from Miami International into London Heathrow reached the gate within 15 minutes of schedule, across 1,878 flights. 44% arrived more than 15 minutes early, which is normal for an eastbound crossing with the jet stream behind it and a schedule padded for the days it is not. 0.73% of those arrivals were three hours or more late, the figure that decides a compensation claim on the return trip, and 1.7% were cancelled.
Arrived on time
79.9%
Within 15 minutes, of 1,878 arrivals
Early
44.2%
More than 15 minutes ahead of schedule
Cancelled
1.73%
3+ hours late
0.73%
Arrival delay, the compensation test
- Early15+ min early44.2%
- On timeup to 15 min late35.7%
- 16–30 min5.8%
- 31–60 min6.6%
- 1–2 hours4.3%
- 2–3 hours1.1%
- 3–6 hourscompensation threshold0.5%
- Over 6 hours0.3%
Scale runs 0% to 100%.
The departure airport
How London Heathrow is running
EUROCONTROL's figures for London Heathrow as a whole, every airline and every destination: 80.3% of departures and 80.5% of arrivals within 15 minutes of schedule from 1 January to 21 October 2026, with 96.7% of scheduled flights operated. The last seven days ran at 80.8% for departures, in line with the year. Air traffic flow management delay attributed to the airport averaged 1.2 minutes per arriving flight this year, 1.0 over the last week.
| Window | Departures on time | Arrivals on time | Schedules operated | ATFM delay / arrival |
|---|---|---|---|---|
| Yesterday (21 October 2026) | 77.2% | 80.6% | 98.2% | 2.8 min |
| Last 7 days | 80.8% | 84.1% | 98.1% | 1.0 min |
| Year to date | 80.3% | 80.5% | 96.7% | 1.2 min |
Every US route from London Heathrow, and its full punctuality record
The arrival airport
Landing at Miami International
Miami International is scored on this site from the DOT's domestic data: 74.2% of its 111,132 domestic departures arrived on time over the last twelve months, with delayed flights running a little over an hour late, and 1.64% were cancelled. Those are domestic flights, not this route, but an arriving transatlantic flight shares the same runways, the same weather and the same ground delay programmes, so a bad day at MIA reaches a flight from LHR just as surely. The airport's own page has the hour-by-hour and month-by-month detail, and its live FAA status appears above when the FAA has something to say.
Domestic on time
74.2%
Arrivals under 15 minutes late (DOT)
Avg delay
72 min
Delayed domestic flights only
Cancelled
1.64%
Domestic departures
111,132
Last twelve months
Miami International (MIA) delay statistics, hour by hour and month by month
Your rights
UK261 on LHR to MIA
Every flight that departs London Heathrow falls under UK261, the retained version of the EU regulation, whichever airline flies it and wherever it lands. If it arrives at Miami International three hours or more late, or is cancelled with under 14 days' notice, and the cause was within the airline's control, each passenger is owed £520 (£260 if the airline got you there under four hours late), on top of rebooking and care. Weather, air traffic control restrictions and strikes outside the airline are the usual exemptions. The return flight from MIA is covered only when the carrier is UK or EU based. The sector is about 4,417 miles, 7,107 km, which puts it in the top distance band.
Delayed three hours or more? Check a claim with Compensair →
What to do with this
Booking LHR to MIA
Booked blind, LHR to MIA is a C route by the departure record. Booked with the numbers, it is American Airlines at 82.4%, outside July if the dates are flexible, and a connection at MIA with at least two hours in hand, because 5% of departures were an hour or more late and immigration comes before any onward flight.
Common questions
LHR to MIA questions
How often are LHR to MIA flights delayed?
About one flight in four leaves London Heathrow at least 15 minutes behind schedule, 26.1% of the 1,878 departures the CAA matched between September 2025 and August 2026. 5.3% left more than an hour late and 0.69% three hours or more. A further 1.9% of scheduled departures were cancelled.
Which airline is most punctual from LHR to MIA?
American Airlines, at 82.4% of departures within 15 minutes across 543 flights. British Airways is lowest at 63.1%. British Airways also cancelled more often, 1.5% against 1.3%.
Can I claim compensation for a delayed LHR to MIA flight?
Yes, if the flight arrived three hours or more late or was cancelled at short notice for a reason within the airline's control: departures from London Heathrow are covered by UK261 whichever airline operates them. The fixed amount for a sector of this length is £520 a passenger, £260 if the airline got you there under four hours late. On this route 0.69% of departures left three hours or more late over the last twelve months. The return from MIA is covered only on a UK or EU carrier.
What is the worst month for delays on LHR to MIA?
July, at 65.3% of departures on time, against 84.5% in February, the best month. A gap that size is worth moving flexible dates for.
Related
Where to go next
- London Heathrow (LHR): every US route
- Miami International (MIA) delay statistics
- LHR to JFK, New York (JFK)14,572 flights
- LHR to EWR, Newark (EWR)6,322 flights
- LHR to LAX, Los Angeles (LAX)5,981 flights
- LHR to ORD, Chicago (ORD)5,762 flights
- MAD to MIA, from Madrid2,708 flights
- CDG to MIA, from Paris1,419 flights
- BCN to MIA, from Barcelona1,171 flights
- FCO to MIA, from Rome1,089 flights
- Every Europe-to-US route and airport
The departure record is the CAA's, measured at London Heathrow; the arrival record for the return leg is also measured at London Heathrow. Nothing here is measured at MIA, where the DOT keeps no record of international flights.
Sources: US DOT Bureau of Transportation Statistics, International Report (flights and passengers by carrier and airport pair), July 2025 to June 2026; UK Civil Aviation Authority punctuality statistics, September 2025 to August 2026; EUROCONTROL Aviation Intelligence Portal, airport punctuality and ATFM delay to 21 October 2026. Rebuilt 22 October 2026; the EUROCONTROL figures refresh with each weekly build, the others when their publisher releases a month. How these sources differ.