Cheapest return flights from Seattle to London in December from $749

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

Return flights

06 Dec - 13 Dec Icelandair
15 Dec - 22 Dec Icelandair
13 Dec - 01 Jan Icelandair
13 Dec - 04 Jan Alaska Airlines
26 Dec - 02 Jan Icelandair
20 Dec - 03 Jan Sun Country Airlines
20 Dec - 31 Dec Icelandair
19 Dec - 02 Jan Icelandair
20 Dec - 04 Jan Icelandair

Also check the deals for one-way 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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