Cheapest one-way flights from Seattle to London in December from $241

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

One-Way flights

05 Dec Frontier Airlines
07 Dec Frontier Airlines
08 Dec Frontier Airlines
10 Dec Icelandair
29 Dec Icelandair
09 Dec Icelandair
14 Dec Frontier Airlines
15 Dec Hawaiian Airlines
25 Dec Frontier Airlines
26 Dec Turkish Airlines

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

Powered by

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.

Book a cheap hotel in London

Cheap car rent in London

Feel free to contact us with any feedback or request another flight research.