Cheapest return flights from Portland to Keflavik in September from $651

Best time to book flights for Portland (PDX) to Keflavik (KEF) flights at AirHint

AirHint found the following cheapest return flights from Portland (PDX) to Keflavik (KEF) in September 2025 (see full year).

Return flights

26 Sep - 12 Oct Icelandair direct
24 Sep - 01 Oct Air Canada
07 Sep - 15 Sep Alaska Airlines
24 Sep - 02 Oct Air France
17 Sep - 02 Oct Air France
21 Sep - 06 Oct Air France
22 Sep - 07 Oct Air France
24 Sep - 01 Oct Icelandair direct
25 Sep - 03 Oct Delta
24 Sep - 02 Oct Icelandair direct
17 Sep - 02 Oct Icelandair direct
14 Sep - 22 Sep Air France
08 Sep - 23 Sep Air France
04 Sep - 19 Sep Air France
14 Sep - 29 Sep Air France
15 Sep - 30 Sep Air France
01 Sep - 16 Sep Air France
11 Sep - 19 Sep Air France
18 Sep - 26 Sep Air France
16 Sep - 24 Sep Air France

Also check the deals for one-way flights from Portland to Keflavik in September.

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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