Cheapest return flights from Chicago to Keflavik in September from 461€

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

Return flights

25 Sep - 26 Sep Spirit Airlines
25 Sep - 02 Oct Delta
29 Sep - 07 Oct KLM
30 Sep - 07 Oct KLM
16 Sep - 23 Sep Frontier Airlines
19 Sep - 23 Sep Frontier Airlines
27 Sep - 04 Oct Frontier Airlines
15 Sep - 11 Oct Frontier Airlines
26 Sep - 28 Sep Frontier Airlines
25 Sep - 28 Sep Frontier Airlines
30 Sep - 05 Oct Frontier Airlines
30 Sep - 02 Oct Frontier Airlines
17 Sep - 19 Sep Spirit Airlines
15 Sep - 19 Sep Frontier Airlines
18 Sep - 25 Sep Spirit Airlines
29 Sep - 03 Oct Frontier Airlines
29 Sep - 03 Oct Icelandair direct
18 Sep - 21 Sep Spirit Airlines
27 Sep - 29 Sep Frontier Airlines
30 Sep - 02 Oct Icelandair direct

Also check the deals for one-way flights from Chicago 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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