Cheapest return flights from Seattle to Keflavik in August from 684€

Best time to book flights for Seattle (SEA) to Keflavik (KEF) flights at AirHint

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

Return flights

23 Aug - 02 Sep United
28 Aug - 07 Sep Air Canada
30 Aug - 16 Sep United
27 Aug - 06 Sep United
23 Aug - 01 Sep United
15 Aug - 26 Aug United
11 Aug - 31 Aug United
22 Aug - 01 Sep United
26 Aug - 01 Sep Alaska Airlines
21 Aug - 27 Aug Icelandair direct
22 Aug - 01 Sep Icelandair direct
23 Aug - 02 Sep Icelandair direct
27 Aug - 06 Sep Icelandair direct
11 Aug - 31 Aug Icelandair direct
10 Aug - 20 Aug Icelandair direct
17 Aug - 25 Aug Icelandair direct
10 Aug - 18 Aug Icelandair direct
05 Aug - 11 Aug jetBlue

Also check the deals for one-way 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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