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

Return flights

18 Sep - 25 Sep	Wizz Air
25 Sep - 09 Oct	Wizz Air
26 Sep - 28 Sep	Wizz Air
26 Sep - 06 Oct	Wizz Air Malta
17 Sep - 24 Sep	Wizz Air Malta
23 Sep - 28 Sep	Wizz Air
18 Sep - 24 Sep	Wizz Air
20 Sep - 27 Sep	Wizz Air
29 Sep - 07 Oct	Wizz Air
23 Sep - 25 Sep	SKY express
16 Sep - 20 Sep	Scandinavian Airlines
16 Sep - 23 Sep	Scandinavian Airlines
29 Sep - 05 Oct	Ryanair
30 Sep - 07 Oct	Ryanair
19 Sep - 25 Sep	Wizz Air
28 Sep - 05 Oct	SKY express
29 Sep - 08 Oct	Wizz Air Malta
28 Sep - 08 Oct	SKY express
20 Sep - 01 Oct	Ryanair

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

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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Cheapest return flights from Athens to Keflavik in September from $304

Return flights