Cheapest return flights from Seattle to Keflavik in August from $503

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

06 Aug - 13 Aug WestJet
22 Aug - 29 Aug WestJet
28 Aug - 08 Sep Icelandair direct
29 Aug - 02 Sep Icelandair direct
06 Aug - 13 Aug Icelandair direct
18 Aug - 25 Aug WestJet
05 Aug - 12 Aug WestJet
13 Aug - 20 Aug WestJet
03 Aug - 08 Aug WestJet
10 Aug - 15 Aug WestJet
02 Aug - 09 Aug WestJet
26 Aug - 01 Sep Icelandair direct
04 Aug - 09 Aug WestJet
27 Aug - 01 Sep Icelandair direct
31 Aug - 07 Sep Icelandair direct
28 Aug - 04 Sep Icelandair direct
29 Aug - 05 Sep Icelandair direct
26 Aug - 02 Sep Icelandair direct
27 Aug - 03 Sep Icelandair direct
25 Aug - 02 Sep Icelandair direct

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.

Book a cheap hotel in Keflavik

Cheap car rent in Keflavik