Cheapest return flights from San Francisco to Keflavik in September from $608

Best time to book flights for San Francisco (SFO) to Keflavik (KEF) flights at AirHint

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

Return flights

08 Sep - 16 Sep Alaska Airlines
02 Sep - 10 Sep Alaska Airlines
03 Sep - 11 Sep Alaska Airlines
03 Sep - 10 Sep Alaska Airlines
09 Sep - 17 Sep Alaska Airlines
15 Sep - 23 Sep Alaska Airlines
10 Sep - 18 Sep Alaska Airlines
23 Sep - 01 Oct Alaska Airlines
24 Sep - 02 Oct Alaska Airlines
19 Sep - 27 Sep Alaska Airlines
08 Sep - 15 Sep Hawaiian Airlines
14 Sep - 22 Sep Alaska Airlines
25 Sep - 03 Oct Alaska Airlines
27 Sep - 04 Oct Hawaiian Airlines
30 Sep - 08 Oct Hawaiian Airlines
29 Sep - 07 Oct Hawaiian Airlines
28 Sep - 06 Oct Scandinavian Airlines
26 Sep - 04 Oct jetBlue
27 Sep - 05 Oct Hawaiian Airlines

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

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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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