Cheapest return flights from Seattle to London in October from $599

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 October 2025 (see full year).

Return flights

07 Oct - 16 Oct Aer Lingus
07 Oct - 16 Oct Iberia direct
01 Oct - 30 Oct Iberia
01 Oct - 30 Oct British Airways direct
06 Oct - 18 Oct Iberia direct
21 Oct - 28 Oct United
01 Oct - 08 Oct United
31 Oct - 07 Nov United
11 Oct - 18 Oct United

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

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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