Cheapest return flights from Seattle to London in September from 396€

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

Return flights

02 Sep - 16 Sep Aer Lingus
02 Sep - 26 Sep Aer Lingus
03 Sep - 26 Sep Aer Lingus
02 Sep - 17 Sep Aer Lingus
03 Sep - 11 Sep Aer Lingus
14 Sep - 26 Sep Aer Lingus
09 Sep - 16 Sep Aer Lingus
30 Sep - 21 Oct Aer Lingus
06 Sep - 13 Sep Icelandair
01 Sep - 15 Sep Icelandair
09 Sep - 30 Sep Delta
30 Sep - 07 Oct British Airways direct
24 Sep - 01 Oct British Airways direct
30 Sep - 21 Oct Virgin Atlantic direct
27 Sep - 11 Oct Icelandair
11 Sep - 30 Oct Air France
04 Sep - 30 Oct Air France
11 Sep - 30 Oct British Airways direct
04 Sep - 30 Oct British Airways direct
27 Sep - 05 Oct Delta

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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