AirHint found the following cheapest one-way flights from Washington (IAD) to London (LHR) in December 2025 (see full year).
One-Way flights
| 08 Dec | TAP | ||
| 28 Dec | TAP | ||
| 24 Dec | Icelandair | ||
| 15 Dec | Icelandair | ||
| 25 Dec | TAP | ||
| 08 Dec | British Airways | direct | |
| 12 Dec | Iberia | direct | |
| 24 Dec | United | direct | |
| 14 Dec | United | direct | |
| 16 Dec | United |
Also check the deals for return flights from Washington to London in December.
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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