Cheapest one-way flights from Seattle to Keflavik in September from 256€

AirHint found the following cheapest one-way flights from Seattle (SEA) to Keflavik (KEF) in September 2025 (see full year).

One-Way flights

17 Sep WestJet
30 Sep Hawaiian Airlines
30 Sep Icelandair direct
17 Sep Icelandair direct

Also check the deals for return flights from Seattle to Keflavik in September.

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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