Cheapest one-way flights from Seattle to London in December from $272

AirHint found the following cheapest one-way flights from Seattle (SEA) to London (LGW) in December 2025 (see full year).

One-Way flights

04 Dec Hawaiian Airlines
06 Dec Hawaiian Airlines
03 Dec Icelandair
16 Dec Icelandair
26 Dec WestJet
27 Dec Alaska Airlines
20 Dec Sun Country Airlines
19 Dec Sun Country Airlines
17 Dec Sun Country Airlines

Also check the deals for return flights from Seattle to London in December.

Skyscanner

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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