$129 Cheap American Airlines flights Ontario (ONT) to San Francisco (SFO)

Landing cheap one-way American Airlines flights from ONT to SFO from $129 on Expedia couldn't be simpler — just filter by "Price (lowest to highest)." Alternatively, check out our budget-friendly round-trip fares from $247 for your next break.**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.

For cheap American Airlines fares from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO), start searching one to three months before your planned departure. Reserving domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also influence the cost. Sunday is generally the most affordable, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your journey on a Sunday.**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.

Search American Airlines's earliest flights from ONT to SFO by checking the "Early Morning" and "Morning" filters. Not only will you get to where you're going 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.