Cheapest one-way flights from Seattle to Keflavik in August from 276€

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

One-Way flights

26 Aug WestJet
05 Aug Spirit Airlines
11 Aug Spirit Airlines
23 Aug Frontier Airlines
18 Aug Frontier Airlines
15 Aug Frontier Airlines
16 Aug Frontier Airlines
20 Aug Frontier Airlines
02 Aug Frontier Airlines
23 Aug Icelandair direct

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

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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