Cheapest return flights from San Francisco to Keflavik in September from $532

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

09 Sep - 16 Sep Alaska Airlines
10 Sep - 17 Sep Alaska Airlines
15 Sep - 23 Sep Alaska Airlines
09 Sep - 19 Sep jetBlue
14 Sep - 22 Sep WestJet
13 Sep - 21 Sep Hawaiian Airlines
11 Sep - 18 Sep United
01 Sep - 08 Sep Air France
06 Sep - 13 Sep United

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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