Cheapest one-way flights from Seattle to London in April from $281

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

One-Way flights

22 Apr WestJet
21 Apr WestJet
08 Apr Icelandair
05 Apr Icelandair
03 Apr Alaska Airlines
01 Apr Air Canada
22 Apr British Airways direct
21 Apr British Airways direct
01 Apr Air France direct
08 Apr Air France direct

Also check the deals for return 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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