Cheapest return flights from Seattle to Keflavik in October from $595

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

Return flights

11 Oct - 18 Oct Austrian Airlines
18 Oct - 25 Oct Air France
23 Oct - 09 Nov Lufthansa
05 Oct - 16 Oct Lufthansa
07 Oct - 14 Oct Alaska Airlines
01 Oct - 14 Oct Air Canada
15 Oct - 25 Oct Lufthansa
06 Oct - 12 Oct WestJet
09 Oct - 15 Oct Sun Country Airlines
02 Oct - 11 Oct Hawaiian Airlines
01 Oct - 06 Oct Icelandair direct
30 Oct - 06 Nov Icelandair direct
27 Oct - 03 Nov Icelandair direct
23 Oct - 09 Nov Icelandair direct

Also check the deals for one-way flights from Seattle to Keflavik in October.

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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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