Transatlantic route record · UK CAA departure punctuality
LHR→SLC
London to Salt Lake City
- Flights
- 506 both ways
- Carriers
- 1
- Distance
- 4,853 mi
- Period
- September 2025 to August 2026
Over the twelve months to August 2026, 80.0% of departures from London Heathrow to Salt Lake City International left within 15 minutes of their planned time, from 257 flights the UK Civil Aviation Authority matched to a schedule. That is 4 points ahead of the 76.4% recorded across every UK departure to the United States, and it ranks 9th of the 50 UK-to-US routes with a usable record. About one flight in five left at least 15 minutes behind schedule, and 3 of 260 scheduled departures, 1.1%, did not operate at all.
The route's 80.0% is an improvement of 4 points on the same months a year earlier, when 76.4% 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. A single carrier accounts for almost every departure, so the route figure and the airline figure are the same number.
Key figures
Left on time
80.0%
Within 15 minutes of schedule, of 257 departures (CAA)
Avg delay
12 min
Across all departures, early counted as zero
Cancelled
1.15%
All UK-to-US departures: 2.16%
3+ hours late
0.00%
The UK261 compensation threshold
6.9% of departures left more than an hour late, and 0.00% left three hours or more behind schedule, almost no flights. 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 11.9 minutes, against 14.2 for all UK-to-US departures.
Carrier by carrier
Which airline leaves LHR for SLC on time
Delta Air Lines is the only carrier the DOT report shows on LHR to SLC, with 506 flights and an average of 181 passengers aboard each. A single-carrier route gives a delayed passenger no same-day alternative on the same ticket, which is worth knowing before booking a tight onward connection.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Linesthin sample | 260 | 80.0% | 12 min | 1.15% | B |
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 SLC are distributed
- Early15+ min early0.0%
- On timeup to 15 min late80.0%
- 16–30 min6.2%
- 31–60 min5.7%
- 1–2 hours5.8%
- 2–3 hours1.1%
- 3–6 hourscompensation threshold0.0%
- Over 6 hours0.0%
Scale runs 0% to 100%.
Across the year
When LHR to SLC runs late
November was the weakest month for departures at 68.2% on time and March the strongest at 90.9%, a swing of 23 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 44 flights in October 2025 and the thinnest at 36 in February 2026, so capacity follows the summer peak.
Flights per month, both directions
- July 202543
- August 202540
- September 202543
- October 202544
- November 202543
- December 202543
- January 202640
- February 202636
- March 202644
- April 202643
- May 202644
- June 202643
The DOT's international report counts flights in both directions together: 506 between LHR and SLC from July 2025 to June 2026, about five departures a week in each direction, carrying 91,584 passengers. That makes it the 29th busiest of 31 US routes from London Heathrow and the 3rd busiest of 3 European routes into SLC.
The return leg
SLC to LHR: arrivals back into London
Coming the other way, 78.7% of arrivals from Salt Lake City International into London Heathrow reached the gate within 15 minutes of schedule, across 255 flights. 28% 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. 1.16% of those arrivals were three hours or more late, the figure that decides a compensation claim on the return trip, and 2.3% were cancelled.
Arrived on time
78.7%
Within 15 minutes, of 255 arrivals
Early
28.4%
More than 15 minutes ahead of schedule
Cancelled
2.30%
3+ hours late
1.16%
Arrival delay, the compensation test
- Early15+ min early28.4%
- On timeup to 15 min late50.4%
- 16–30 min7.6%
- 31–60 min6.1%
- 1–2 hours2.7%
- 2–3 hours1.5%
- 3–6 hourscompensation threshold0.8%
- Over 6 hours0.4%
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 Salt Lake City International
Salt Lake City International is scored on this site from the DOT's domestic data: 84.2% of its 117,966 domestic departures arrived on time over the last twelve months, with delayed flights running about an hour late, and 0.77% 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 SLC 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
84.2%
Arrivals under 15 minutes late (DOT)
Avg delay
65 min
Delayed domestic flights only
Cancelled
0.77%
Domestic departures
117,966
Last twelve months
Salt Lake City International (SLC) delay statistics, hour by hour and month by month
Your rights
UK261 on LHR to SLC
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 Salt Lake City 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 SLC is covered only when the carrier is UK or EU based. The sector is about 4,853 miles, 7,808 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 SLC
Booked blind, LHR to SLC is a B route by the departure record, and there is no carrier choice to make. Leave at least two hours for any onward connection at SLC: 7% of departures were an hour or more late, and immigration comes before the connecting flight.
Common questions
LHR to SLC questions
How often are LHR to SLC flights delayed?
About one flight in five leaves London Heathrow at least 15 minutes behind schedule, 20.0% of the 257 departures the CAA matched between September 2025 and August 2026. 6.9% left more than an hour late and 0.00% three hours or more. A further 1.1% of scheduled departures were cancelled.
Which airlines fly LHR to SLC?
Delta Air Lines. Delta Air Lines accounted for 100% of the 506 flights the DOT counted on the pair.
Can I claim compensation for a delayed LHR to SLC 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 0.00% of departures left three hours or more late over the last twelve months. The return from SLC is covered only on a UK or EU carrier.
What is the worst month for delays on LHR to SLC?
November, at 68.2% of departures on time, against 90.9% in March, the best month. A gap that size is worth moving flexible dates for.
Related
Where to go next
- London Heathrow (LHR): every US route
- Salt Lake City International (SLC) 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
- AMS to SLC, from Amsterdam919 flights
- CDG to SLC, from Paris691 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 SLC, 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.