Cheapest return flights from Seattle to London in October from $518

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 October 2025 (see full year).

Return flights

08 Oct - 26 Oct Icelandair
08 Oct - 15 Oct Icelandair
08 Oct - 23 Oct Icelandair
09 Oct - 23 Oct Icelandair
12 Oct - 26 Oct Icelandair
03 Oct - 16 Oct Icelandair
04 Oct - 11 Oct Icelandair
01 Oct - 16 Oct Icelandair
13 Oct - 16 Oct Aer Lingus
29 Oct - 05 Nov Icelandair
14 Oct - 21 Oct United
29 Oct - 05 Nov British Airways direct

Also check the deals for one-way flights from Seattle to London in October.

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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