AirHint found the following cheapest one-way flights from Seattle (SEA) to London (LHR) in January 2026 (see full year).
One-Way flights
| 19 Jan | WestJet | ||
| 24 Jan | Air Canada | ||
| 26 Jan | WestJet | ||
| 22 Jan | WestJet | ||
| 23 Jan | WestJet | ||
| 14 Jan | Alaska Airlines | ||
| 20 Jan | Alaska Airlines | ||
| 30 Jan | Alaska Airlines | ||
| 15 Jan | Air Canada | ||
| 16 Jan | Alaska Airlines |
Also check the deals for return flights from Seattle to London in January.
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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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