AirHint found the following cheapest return flights from Seattle (SEA) to Lisbon (LIS) in January 2026 (see full year).

Return flights

21 Jan - 29 Jan	Icelandair
10 Jan - 18 Jan	Icelandair
14 Jan - 22 Jan	Icelandair
17 Jan - 25 Jan	Icelandair
24 Jan - 01 Feb	Icelandair
28 Jan - 05 Feb	Icelandair
31 Jan - 08 Feb	Icelandair
05 Jan - 04 Feb	Air Canada
14 Jan - 21 Jan	British Airways
13 Jan - 21 Jan	British Airways
10 Jan - 31 Jan	Air Canada
08 Jan - 15 Jan	United
12 Jan - 19 Jan	United
15 Jan - 22 Jan	United
26 Jan - 02 Feb	United
29 Jan - 05 Feb	United
31 Jan - 07 Feb	United
25 Jan - 02 Feb	United
30 Jan - 07 Feb	United
27 Jan - 03 Feb	United

Also check the deals for one-way flights from Seattle to Lisbon in January.

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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Cheapest return flights from Seattle to Lisbon in January from $484

Return flights