Flights Washington → London — September 12, 2026

One way · Economy · 1 adult · price per person

The cheapest itinerary observed for Saturday, September 12, 2026 on the Washington–London route: 1 stop itinerary (2 flights) via Newark Liberty (EWR), from Washington Dulles (IAD) to London Heathrow (LHR), first flight United Airlines UA1997, departs 10:41 PM, arrives 8:40 PM the next day, total travel time 16h 59m including layovers, flight time 8h 38m (layovers excluded), $507 per person. Fare as listed by Aviasales: carry-on bag not included (personal item only), checked bag not included, changes allowed for a fee, non-refundable. Price found in an Aviasales search on September 10, 2026 and read by AirSource on September 10, 2026, 19:00 UTC: it is not guaranteed and is confirmed on Aviasales at booking time. The cheapest direct flight observed: United Airlines UA918, from Washington Dulles (IAD) to London Heathrow (LHR), departs 6:35 PM, arrives 6:55 AM the next day, direct, 7h 20m, $570 per person. Fare as listed by Aviasales: carry-on bag not included (personal item only), checked bag not included, changes allowed for a fee, non-refundable.