Cheapest return flights from Seattle to London in April from 438€

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

Return flights

04 Apr - 12 Apr Icelandair
25 Apr - 03 May Icelandair
02 Apr - 09 Apr Icelandair
01 Apr - 08 Apr Icelandair
07 Apr - 14 Apr Icelandair
14 Apr - 09 May Icelandair
17 Apr - 24 Apr Icelandair
01 Apr - 10 Apr Delta
29 Apr - 13 May United
22 Apr - 04 May Delta
22 Apr - 29 Apr British Airways direct
13 Apr - 27 Apr Icelandair
01 Apr - 25 Apr Air France
27 Apr - 04 May Icelandair
17 Apr - 24 Apr British Airways direct
14 Apr - 09 May Air France direct
27 Apr - 04 May British Airways direct
22 Apr - 04 May British Airways direct

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

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