Cheapest return flights from Seattle to London in April from $552

Best time to book flights for Seattle (SEA) to London (LHR) flights at AirHint

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

Return flights

25 Apr - 27 Apr Lufthansa
29 Apr - 05 May Icelandair
22 Apr - 27 Apr Icelandair
23 Apr - 30 Apr Icelandair
24 Apr - 28 Apr Icelandair
08 Apr - 22 Apr Aer Lingus
01 Apr - 09 Apr Aer Lingus
07 Apr - 11 Apr Aer Lingus
01 Apr - 10 Apr Aer Lingus
07 Apr - 15 Apr Aer Lingus
08 Apr - 15 Apr Aer Lingus
22 Apr - 06 May Aer Lingus
21 Apr - 01 May Aer Lingus
22 Apr - 06 May Iberia direct
21 Apr - 01 May Iberia direct
25 Apr - 05 May Icelandair
24 Apr - 05 May Icelandair
25 Apr - 04 May Lufthansa
29 Apr - 22 May Finnair
30 Apr - 22 May Aer Lingus

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

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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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