Cheapest return flights from Seattle to London in December from 702€

Best time to book flights for Seattle (SEA) to London (LHR) flights at AirHint

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

Return flights

05 Dec - 11 Dec Icelandair
05 Dec - 13 Dec Icelandair
05 Dec - 13 Dec British Airways direct
24 Dec - 07 Jan Icelandair
05 Dec - 11 Dec Finnair direct
24 Dec - 07 Jan British Airways direct
25 Dec - 02 Jan Lufthansa
25 Dec - 02 Jan British Airways direct

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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