Cheapest return flights from Washington to London in December from $428

Best time to book flights for Washington (IAD) to London (LHR) flights at AirHint

AirHint found the following cheapest return flights from Washington (IAD) to London (LHR) in December 2025 (see full year).

Return flights

02 Dec - 09 Dec Scandinavian Airlines
03 Dec - 11 Dec Scandinavian Airlines
03 Dec - 08 Dec Scandinavian Airlines
02 Dec - 13 Dec Scandinavian Airlines
01 Dec - 14 Dec Scandinavian Airlines
02 Dec - 14 Dec Scandinavian Airlines
03 Dec - 14 Dec Scandinavian Airlines
03 Dec - 06 Dec TAP
03 Dec - 24 Dec TAP
02 Dec - 24 Dec TAP
24 Dec - 18 Jan TAP
24 Dec - 14 Jan TAP
24 Dec - 17 Jan TAP
30 Dec - 09 Jan Icelandair
23 Dec - 13 Jan Icelandair
23 Dec - 11 Jan Icelandair
09 Dec - 02 Jan Air Canada
30 Dec - 09 Jan British Airways direct
17 Dec - 09 Jan Aer Lingus
16 Dec - 06 Jan Icelandair

Also check the deals for one-way flights from Washington to London in December.

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The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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