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LHR to IAD

London to Washington flights

Flights from London Heathrow (LHR) to Washington Dulles (IAD) cover 5,902 km. 3,897 flights flew between them in the last 12 months of UK Civil Aviation Authority figures; 76% were on time across 3 airlines.

3,897
flights, August 2025 to July 2026
76%
on time (within 15 min)
2.6%
cancelled
+15 min
average delay

Both directions together. On time means within 15 minutes of schedule, counted over every scheduled flight to and from the UK airport, including cancelled ones (the CAA's definition).

Airlines on this route

AirlineFlightsOn timeCancelledAverage delay
British Airways1,79076%2.3%15 min
United Airlines1,43373%2.2%19 min
Virgin Atlantic Airways67480%4.2%10 min

Month by month

Over the last 12 months, London and Washington ran best in March 2026 (83% on time) and worst in July 2026 (66.9%).

Share of flights on time, by month (UK Civil Aviation Authority). Green is the best month, orange the worst.
See the figures
MonthOn timeCancelledFlights
August 202571%2.5%364
September 202576%0.6%358
October 202577%0.9%337
November 202579%1.4%296
December 202572%2.7%295
January 202678%5%279
February 202682%2.4%248
March 202683%2.3%300
April 202680%4%346
May 202674%1.6%366
June 202672%4.3%349
July 202667%3.6%359

Source: UK Civil Aviation Authority punctuality statistics, August 2025 to July 2026. Contains UK Civil Aviation Authority data. Figures describe the past and do not predict a future flight.

More about London Heathrow (LHR) and Washington Dulles (IAD).

Questions and answers

How often are flights between London and Washington on time?
75.6% of 3,897 flights were on time (within 15 minutes) over the last 12 months of UK Civil Aviation Authority figures, and 2.6% were cancelled.
Which airline is most punctual between London and Washington?
Virgin Atlantic Airways, with 80.3% on time. United Airlines was the least punctual at 73.3%.
What is the best month to fly between London and Washington?
Over the last 12 months, London and Washington ran best in March 2026 (83% on time) and worst in July 2026 (66.9%).

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