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DelayAtlas

Transatlantic route record · UK CAA departure punctuality

LHR→BWI

London to Baltimore

Flights
664 both ways
Carriers
1
Distance
3,625 mi
Period
September 2025 to August 2026
DGRADE

Over the twelve months to August 2026, 63.9% of departures from London Heathrow to Baltimore/Washington International Thurgood Marshall left within 15 minutes of their planned time, from 332 flights the UK Civil Aviation Authority matched to a schedule. That is 13 points behind the 76.4% recorded across every UK departure to the United States, and it ranks 46th of the 50 UK-to-US routes with a usable record. About one flight in three left at least 15 minutes behind schedule, and 7 of 339 scheduled departures, 2.1%, did not operate at all.

The route's 63.9% is an improvement of 6 points on the same months a year earlier, when 57.9% 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

63.9%

Within 15 minutes of schedule, of 332 departures (CAA)

Avg delay

19 min

Across all departures, early counted as zero

Cancelled

2.06%

All UK-to-US departures: 2.16%

3+ hours late

0.58%

The UK261 compensation threshold

7.3% of departures left more than an hour late, and 0.58% 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 19.2 minutes, against 14.2 for all UK-to-US departures.

Carrier by carrier

Which airline leaves LHR for BWI on time

British Airways is the only carrier the DOT report shows on LHR to BWI, with 664 flights and an average of 208 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.

CAA departure punctuality by carrier, LHR to BWI
AirlineFlightsOn timeAvg delayCancelledGrade
British Airwaysthin sample33963.9%19 min2.06%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 BWI are distributed

  • Early15+ min early0.0%
  • On timeup to 15 min late63.9%
  • 16–30 min17.4%
  • 31–60 min9.4%
  • 1–2 hours5.6%
  • 2–3 hours1.2%
  • 3–6 hourscompensation threshold0.6%
  • Over 6 hours0.0%

Scale runs 0% to 100%.

Departures from London Heathrow, September 2025 to August 2026. Shares of 332 operated flights; cancellations (7) are outside the bars.

Across the year

When LHR to BWI runs late

August was the weakest month for departures at 51.6% on time and April the strongest at 83.3%, a swing of 32 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 62 flights in August 2025 and the thinnest at 42 in February 2026, so capacity follows the summer peak.

Departure punctuality by month, LHR to BWI62J61F81M83A52M60J67J52A60S52O76N65D
Darker means more delays. Figures are the share of departures within 15 minutes of schedule; a dash is a month with under 20 flights.April best, May worst · 339 flights

Flights per month, both directions

  • July 202560
  • August 202562
  • September 202560
  • October 202560
  • November 202550
  • December 202552
  • January 202650
  • February 202642
  • March 202650
  • April 202659
  • May 202658
  • June 202661
Flights in both directions together, as the DOT international report counts them; flights per calendar month.

The DOT's international report counts flights in both directions together: 664 between LHR and BWI from July 2025 to June 2026, about one departure a day in each direction, carrying 138,434 passengers. That makes it the 26th busiest of 31 US routes from London Heathrow and the 2nd busiest of 2 European routes into BWI.

The return leg

BWI to LHR: arrivals back into London

Coming the other way, 69.6% of arrivals from Baltimore/Washington International Thurgood Marshall into London Heathrow reached the gate within 15 minutes of schedule, across 328 flights. 1.17% of those arrivals were three hours or more late, the figure that decides a compensation claim on the return trip, and 3.5% were cancelled.

Arrived on time

69.6%

Within 15 minutes, of 328 arrivals

Early

14.8%

More than 15 minutes ahead of schedule

Cancelled

3.53%

3+ hours late

1.17%

Arrival delay, the compensation test

  • Early15+ min early14.8%
  • On timeup to 15 min late54.8%
  • 16–30 min12.4%
  • 31–60 min7.3%
  • 1–2 hours4.1%
  • 2–3 hours2.0%
  • 3–6 hourscompensation threshold1.2%
  • Over 6 hours0.0%

Scale runs 0% to 100%.

Arrivals into London Heathrow from Baltimore. Shares of 328 operated flights; cancellations (12) are outside the bars.

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.

EUROCONTROL punctuality at London Heathrow
WindowDepartures on timeArrivals on timeSchedules operatedATFM delay / arrival
Yesterday (21 October 2026)77.2%80.6%98.2%2.8 min
Last 7 days80.8%84.1%98.1%1.0 min
Year to date80.3%80.5%96.7%1.2 min

Every US route from London Heathrow, and its full punctuality record

The arrival airport

Landing at Baltimore/Washington International Thurgood Marshall

Baltimore/Washington International Thurgood Marshall is scored on this site from the DOT's domestic data: 77.1% of its 94,023 domestic departures arrived on time over the last twelve months, with delayed flights running about an hour late, and 1.95% 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 BWI 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

77.1%

Arrivals under 15 minutes late (DOT)

Avg delay

61 min

Delayed domestic flights only

Cancelled

1.95%

Domestic departures

94,023

Last twelve months

Baltimore/Washington International Thurgood Marshall (BWI) delay statistics, hour by hour and month by month

Your rights

UK261 on LHR to BWI

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 Baltimore/Washington International Thurgood Marshall 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 BWI is covered only when the carrier is UK or EU based. The sector is about 3,625 miles, 5,833 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 BWI

Booked blind, LHR to BWI is a D route by the departure record, and there is no carrier choice to make. Leave at least two hours for any onward connection at BWI: 7% of departures were an hour or more late, and immigration comes before the connecting flight.

Common questions

LHR to BWI questions

How often are LHR to BWI flights delayed?

About one flight in three leaves London Heathrow at least 15 minutes behind schedule, 36.1% of the 332 departures the CAA matched between September 2025 and August 2026. 7.3% left more than an hour late and 0.58% three hours or more. A further 2.1% of scheduled departures were cancelled.

Which airlines fly LHR to BWI?

British Airways. British Airways accounted for 100% of the 664 flights the DOT counted on the pair.

Can I claim compensation for a delayed LHR to BWI 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 0.58% of departures left three hours or more late over the last twelve months. The return from BWI is covered only on a UK or EU carrier.

What is the worst month for delays on LHR to BWI?

August, at 51.6% of departures on time, against 83.3% in April, the best month. A gap that size is worth moving flexible dates for.

Related

Where to go next

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 BWI, 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.