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

Return flights

16 Sep - 23 Sep	Spirit Airlines
09 Sep - 16 Sep	Spirit Airlines
17 Sep - 24 Sep	Spirit Airlines
16 Sep - 24 Sep	Spirit Airlines
17 Sep - 25 Sep	Spirit Airlines
10 Sep - 17 Sep	Spirit Airlines
23 Sep - 01 Oct	Spirit Airlines
26 Sep - 04 Oct	Spirit Airlines
19 Sep - 26 Sep	Spirit Airlines
15 Sep - 23 Sep	Spirit Airlines
09 Sep - 20 Sep	Spirit Airlines
12 Sep - 19 Sep	Spirit Airlines
24 Sep - 01 Oct	Spirit Airlines
25 Sep - 02 Oct	Spirit Airlines
24 Sep - 02 Oct	Spirit Airlines
25 Sep - 03 Oct	Frontier Airlines

Also check the deals for one-way flights from Houston 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.

Book a cheap hotel in Keflavik

Cheap car rent in Keflavik

Cheapest return flights from Houston to Keflavik in September from $334

Return flights