Cheapest one-way flights from Ontario to San Jose in September from $154

AirHint found the following cheapest one-way flights from Ontario (ONT) to San Jose (SJO) in September 2025 (see full year).

One-Way flights

27 Sep Avianca
23 Sep Avianca
25 Sep Avianca
28 Sep Frontier Airlines
26 Sep Frontier Airlines
17 Sep Southwest Airlines
30 Sep Southwest Airlines
29 Sep Southwest Airlines
24 Sep Southwest Airlines
11 Sep Avianca

Also check the deals for return flights from Ontario to San Jose 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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