Cheapest one-way flights from Seattle to London in April from $212

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

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

One-Way flights

26 Apr Icelandair
23 Apr Icelandair
28 Apr Icelandair
24 Apr Icelandair
11 Apr Icelandair
07 Apr jetBlue
13 Apr WestJet
08 Apr Air Canada
12 Apr Air Canada
06 Apr Alaska Airlines

Also check the deals for return flights from Seattle to London in April.

Skyscanner

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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