Cheapest return flights from San Francisco (SFO) to Ontario (ONT), September

Select a price to book. see full year.

Dates, airline, and price
Dates Airline Price
01 Sep 05 Sep Frontier Airlines
Direct Flight
18 Sep 25 Sep Frontier Airlines
Direct Flight
04 Sep 07 Sep Frontier Airlines
Direct Flight
06 Sep 30 Sep Frontier Airlines
23 Sep 29 Sep Southwest Airlines
22 Sep 23 Sep Southwest Airlines
22 Sep 29 Sep Southwest Airlines
16 Sep 30 Sep Southwest Airlines
08 Sep 15 Sep Southwest Airlines
22 Sep 03 Oct Southwest Airlines
19 Sep 22 Sep Southwest Airlines
30 Sep 04 Oct Southwest Airlines
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deals for one-way flights from San Francisco to Ontario in September.

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Updated Jul 5, 2026.

About these fares

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