Cheapest return flights from Ontario to San Francisco in October from 66€

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

Return flights

27 Oct - 30 Oct Frontier Airlines direct
17 Oct - 19 Oct Frontier Airlines direct
06 Oct - 08 Oct United direct
25 Oct - 29 Oct Frontier Airlines
22 Oct - 05 Nov Southwest Airlines
21 Oct - 21 Oct Southwest Airlines
07 Oct - 08 Oct Southwest Airlines
01 Oct - 15 Oct Southwest Airlines
22 Oct - 29 Oct Southwest Airlines
19 Oct - 22 Oct United direct
08 Oct - 11 Oct Southwest Airlines
05 Oct - 05 Nov Southwest Airlines
28 Oct - 01 Nov Southwest Airlines
30 Oct - 15 Nov Southwest Airlines
31 Oct - 07 Nov 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.

Book a cheap hotel in San Francisco

Cheap car rent in San Francisco

Feel free to contact us with any feedback or request another flight research.