Cheapest return flights from Seattle to Keflavik in October from $514

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 October 2025 (see full year).

Return flights

12 Oct - 21 Oct Icelandair direct
08 Oct - 15 Oct Icelandair direct
13 Oct - 22 Oct Icelandair direct
05 Oct - 12 Oct Icelandair direct
06 Oct - 13 Oct Icelandair direct
07 Oct - 14 Oct Icelandair direct
10 Oct - 17 Oct Icelandair direct
09 Oct - 16 Oct Icelandair direct
04 Oct - 12 Oct Icelandair direct
04 Oct - 13 Oct Icelandair direct

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

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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