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

AirHint found the following cheapest return flights from Seattle (SEA) to London (LHR) in May 2026 (see full year).

Return flights

12 May - 21 May Icelandair
01 May - 12 May Icelandair
11 May - 06 Jun Icelandair
12 May - 14 May Aer Lingus
12 May - 21 May American Airlines direct
06 May - 18 May Finnair
15 May - 06 Jun Icelandair
01 May - 12 May British Airways direct
06 May - 18 May Air France direct
10 May - 17 May British Airways direct
26 May - 05 Jun Scandinavian Airlines
21 May - 04 Jun Icelandair
20 May - 27 May Icelandair
23 May - 30 May Scandinavian Airlines
30 May - 09 Jun Air Canada
11 May - 06 Jun British Airways direct
19 May - 13 Jun British Airways direct
21 May - 13 Jun Icelandair
21 May - 04 Jun Finnair direct
21 May - 13 Jun British Airways direct

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

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