Cheapest return flights from Seattle (SEA) to London (LHR), April

Select a price to book. see full year.

Dates, airline, and price
Dates Airline Price
01 Apr 08 Apr Icelandair
05 Apr 22 Apr Icelandair
02 Apr 11 Apr Icelandair
02 Apr 07 Apr Icelandair
09 Apr 11 Apr Lufthansa
02 Apr 06 Apr Icelandair
05 Apr 22 Apr British Airways
Direct Flight
01 Apr 08 Apr Finnair
Direct Flight
02 Apr 06 Apr British Airways
Direct Flight
02 Apr 07 Apr British Airways
Direct Flight
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deals for one-way flights from Seattle to London in April.

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Updated Jul 13, 2026.

About these fares

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