AirHint found the following cheapest one-way flights from Portland (PDX) to Keflavik (KEF) in October 2025 (see full year).

One-Way flights

01 Oct	Alaska Airlines
28 Oct	Icelandair	direct
30 Oct	Icelandair	direct
25 Oct	Icelandair	direct
27 Oct	Icelandair	direct
09 Oct	Icelandair	direct
11 Oct	Icelandair	direct
13 Oct	Icelandair	direct
15 Oct	Icelandair	direct
16 Oct	Icelandair	direct

Also check the deals for return flights from Portland to Keflavik in October.

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

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Cheapest one-way flights from Portland to Keflavik in October from $430

One-Way flights