Cheapest return flights from San Francisco to Keflavik in September from 536€

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

Return flights

28 Sep - 05 Oct Frontier Airlines
20 Sep - 26 Sep Frontier Airlines
23 Sep - 30 Sep Air France
16 Sep - 27 Sep Frontier Airlines
11 Sep - 16 Sep Frontier Airlines
18 Sep - 22 Sep Frontier Airlines
19 Sep - 27 Sep Frontier Airlines
17 Sep - 28 Sep Flair Airlines
24 Sep - 28 Sep WestJet
17 Sep - 29 Sep Flair Airlines

Also check the deals for one-way flights from San Francisco 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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