Cheapest return flights from Seattle to London in May from 517€

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

Return flights

05 May - 19 May Finnair
05 May - 12 May Icelandair
06 May - 20 May Icelandair
13 May - 19 May Delta
11 May - 23 May Icelandair
01 May - 12 May Air France
13 May - 19 May British Airways direct
06 May - 20 May British Airways direct
20 May - 27 May Icelandair
01 May - 10 May Lufthansa
31 May - 08 Jun Scandinavian Airlines
30 May - 06 Jun Icelandair
24 May - 01 Jun Icelandair
30 May - 09 Jun Icelandair
27 May - 24 Jun Aer Lingus
25 May - 01 Jun Icelandair
29 May - 26 Jun Aer Lingus
30 May - 06 Jun Finnair direct
18 May - 01 Jun British Airways direct

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

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