Cheapest return flights from Seattle to London in May from $616

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 May 2025 (see full year).

Return flights

01 May - 08 May Air Canada
04 May - 16 May Aer Lingus
03 May - 20 May Air Canada
01 May - 08 May Iberia direct
04 May - 16 May Iberia direct
04 May - 18 May Aer Lingus
03 May - 11 May Air Canada
04 May - 18 May Iberia direct
03 May - 20 May Iberia direct
06 May - 13 May Icelandair
19 May - 04 Jun Icelandair
20 May - 05 Jun Icelandair
21 May - 14 Jun Icelandair
21 May - 12 Jun Icelandair
16 May - 06 Jun Icelandair
13 May - 21 Jun Icelandair
30 May - 08 Jun Icelandair
10 May - 01 Jun Aer Lingus
17 May - 01 Jun Aer Lingus
29 May - 05 Jun Icelandair

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

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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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