Cheapest return flights from Washington to Keflavik in September from $554

Best time to book flights for Washington (IAD) to Keflavik (KEF) flights at AirHint

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

Return flights

13 Sep - 20 Sep Icelandair direct
08 Sep - 15 Sep Air Canada
16 Sep - 21 Sep Icelandair direct
05 Sep - 12 Sep Icelandair direct
30 Sep - 12 Oct Icelandair direct
13 Sep - 18 Sep Icelandair direct
11 Sep - 14 Sep Icelandair direct
08 Sep - 15 Sep Icelandair direct

Also check the deals for one-way flights from Washington 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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