Cheapest return flights from Washington to London in December from $706

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

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

Return flights

29 Dec - 09 Jan Lufthansa
03 Dec - 08 Dec KLM
16 Dec - 23 Dec SWISS
01 Dec - 15 Dec British Airways
02 Dec - 16 Dec British Airways
13 Dec - 23 Dec SWISS
10 Dec - 15 Dec British Airways
27 Dec - 02 Jan SWISS
13 Dec - 03 Jan British Airways
18 Dec - 07 Jan ITA Airways
26 Dec - 09 Jan SWISS

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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