AirHint found the following cheapest one-way flights from Ontario (ONT) to San Juan (SJU) in September 2025 (see full year).
One-Way flights
| 14 Sep | Southwest Airlines | ||
| 15 Sep | jetBlue | ||
| 13 Sep | jetBlue | ||
| 20 Sep | Southwest Airlines | ||
| 12 Sep | Southwest Airlines |
Also check the deals for return flights from Ontario to San Juan in September.
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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