Cheapest one-way flights from Seattle (SEA) to Keflavik (KEF), September

Select a price to book. see full year.

Dates, airline, and price
Dates Airline Price
17 Sep WestJet
18 Sep WestJet
02 Sep Frontier Airlines
22 Sep Frontier Airlines
26 Sep Lufthansa
27 Sep Aer Lingus
27 Sep Icelandair
Direct Flight
22 Sep Icelandair
Direct Flight
18 Sep Icelandair
Direct Flight
26 Sep Icelandair
Direct Flight
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deals for return flights from Seattle to Keflavik in September.

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Updated Jul 18, 2026.

About these fares

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