$94 Cheap American Airlines flights San Francisco (SFO) to Ontario (ONT)

Set the "Price (lowest to highest)" filter on Expedia to search for cheap American Airlines return flights from $187 from SFO to ONT. Affordable one-way fares from $94 are also available.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Start searching one to three months ahead of your departure date to find cheaper fares on American Airlines flights from San Francisco Intl. Airport (SFO) to Los Angeles - Ontario Intl. Airport (ONT). You can save 25% by booking your domestic flight 34 to 86 days in advance versus last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Get the timing right, and you can enjoy significant savings on domestic flights.*Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

Browse American Airlines's earliest flights from SFO to ONT by using the "Early Morning" and "Morning" filters. Not only will you arrive sooner, early departures are also 20% less likely to be canceled.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.