Cheapest return flights from Seattle to London in September from 395€

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

Return flights

29 Sep - 15 Oct Lufthansa
29 Sep - 08 Oct Aer Lingus
30 Sep - 07 Oct Air Canada
29 Sep - 07 Oct Aer Lingus
28 Sep - 08 Oct Air Canada
29 Sep - 07 Oct Virgin Atlantic direct
26 Sep - 05 Oct Icelandair
20 Sep - 30 Sep Virgin Atlantic
09 Sep - 23 Sep Icelandair
28 Sep - 08 Oct Virgin Atlantic direct
14 Sep - 07 Oct Air France
23 Sep - 30 Sep Delta direct
14 Sep - 30 Sep Delta direct
29 Sep - 15 Oct Virgin Atlantic direct
09 Sep - 30 Sep Icelandair
14 Sep - 21 Sep Air France direct
16 Sep - 23 Sep Air France
18 Sep - 22 Sep Virgin Atlantic
25 Sep - 28 Sep Air France direct
26 Sep - 29 Sep Air France direct

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

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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