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

Return flights

29 Sep - 01 Oct	Wizz Air
18 Sep - 24 Sep	KLM
18 Sep - 22 Sep	Ryanair
29 Sep - 05 Oct	Scandinavian Airlines
26 Sep - 02 Oct	Ryanair
04 Sep - 11 Sep	Ryanair
11 Sep - 20 Sep	Ryanair
23 Sep - 24 Sep	Ryanair
18 Sep - 21 Sep	Ryanair
23 Sep - 25 Sep	Ryanair
13 Sep - 21 Sep	Lufthansa
11 Sep - 21 Sep	Lufthansa
02 Sep - 06 Sep	Fly Play	direct
28 Sep - 06 Oct	Wizz Air
26 Sep - 03 Oct	Ryanair
26 Sep - 01 Oct	Ryanair
26 Sep - 02 Oct	Icelandair	direct
22 Sep - 05 Oct	Ryanair
29 Sep - 01 Oct	Icelandair	direct
28 Sep - 06 Oct	Icelandair	direct

Also check the deals for one-way flights from Brussels 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 Brussels to Keflavik in September from $242

Return flights