AirHint found the following cheapest one-way flights from Washington (IAD) to London (LHR) in December 2025 (see full year).
One-Way flights
| 05 Dec | Frontier Airlines | ||
| 03 Dec | Frontier Airlines | ||
| 07 Dec | Scandinavian Airlines | ||
| 01 Dec | TAP | ||
| 08 Dec | TAP | ||
| 04 Dec | Frontier Airlines | ||
| 09 Dec | TAP | ||
| 30 Dec | TAP | ||
| 10 Dec | Icelandair | ||
| 29 Dec | Icelandair |
Also check the deals for return 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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