Cheapest return flights from Ontario to San Francisco in October from $258

Best time to book flights for Ontario (ONT) to San Francisco (SFO) flights at AirHint

AirHint found the following cheapest return flights from Ontario (ONT) to San Francisco (SFO) in October 2025 (see full year).

Return flights

27 Oct - 31 Oct Southwest Airlines
22 Oct - 22 Oct Southwest Airlines
04 Oct - 05 Oct Southwest Airlines
30 Oct - 15 Nov Southwest Airlines
26 Oct - 31 Oct Southwest Airlines
05 Oct - 12 Oct Southwest Airlines
19 Oct - 30 Oct Southwest Airlines
13 Oct - 13 Oct Southwest Airlines
12 Oct - 19 Oct Southwest Airlines

Also check the deals for one-way flights from Ontario to San Francisco in October.

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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