American Airlines offers flights from Saint Louis to Ontario. Browse available flight options and fares between Lambert-St Louis Int'l Airport (STL) and LA/Ontario International Airport (ONT) for business trips, family visits and short getaways.
Compare fares and schedules and choose the option that fits your trip to Ontario (ONT). Prices and availability may change based on travel dates and demand.
Saint Louis (STL)to
Round trip
Economy
Saint Louis (STL)to
Round trip
Economy
Saint Louis (STL)to
Round trip
Economy
Saint Louis (STL)to
Round trip
Economy
Saint Louis (STL)to
Round trip
Economy
Saint Louis (STL)to
Round trip
Economy
Saint Louis (STL)to
Round trip
Economy
Saint Louis (STL)to
Round trip
Economy
*Fares displayed have been collected within the last 24hrs and may no longer be available at time of booking. Some fares listed may include one or more connections that are Basic Economy, which class is subject to additional terms and conditions. Modifying this information may result in a different fare. To find the most updated fare, please visit aa.com. Additional baggage fees and charges for optional products and services may apply.
Saving on flights
Finding lower fares often depends on timing, flexibility and travel demand. These tips can make it easier to compare options and identify flights that fit your plans.
Booking 1 to 3 months ahead can help you find lower fares on flights to Ontario.
Midweek flights, such as Tuesdays or Wednesdays, can sometimes offer lower fares.
Off-peak seasons tend to be more affordable. If travel demand is higher during holidays or major events, consider less busy times for lower fares.
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Before your flight
Review these tips to prepare for your trip and get ready for your departure.
When to arrive
Arrive at least 2 hours before domestic flights. For international travel, plan for 3 hours before departure.
Check-in
Check in online or on the American app to download your boarding pass or print it before you arrive.
Flight info
Check your terminal and gate before you go and watch for updates in the app or on airport displays.
Documents
Bring a valid ID to pass through security. Make sure your travel details match your identification.
Airport experience
Allow extra time to reach your gate and get through security before boarding begins.
Amenities
Many airports offer dining, charging stations and other services to help you prepare for your trip before boarding.
Airport information
American flies to Ontario International Airport (ONT), located about 4 miles east of downtown Ontario and 35 miles east of downtown Los Angeles. The airport offers convenient access to the Inland Empire and surrounding areas.
Getting from the airport
Several ground transportation options are available between ONT and downtown Ontario or Los Angeles.
For more transportation details, visit Ontario International Airport’s official website.
Omnitrans bus service and Metrolink trains connect ONT with Ontario, Los Angeles, and other regional destinations.
Many hotels offer shuttle service to and from ONT.
Taxis and app-based rideshare services are available at designated pickup areas.
On-site rental car facilities offer options for travelers who prefer to drive.
Upgrade options
Make your trip more comfortable with Main Cabin Extra. Discover how Main Cabin Extra can enhance your trip.
More space with seats at the front of the Main Cabin or in exit rows.
Preferred Group 5 boarding allows easier access to overhead bins.
Enjoy beer, wine and spirits on flights with full beverage service.
Quick answers
Use the fare calendar and flight search tools on this page to compare prices across different travel dates. Adjusting your departure or return date may help you find more flight options and fares that fit your budget.
AAdvantage® members can earn miles on eligible American Airlines flights. Miles can be used toward future travel, upgrades and other rewards. Learn more about the AAdvantage® program.
When planning your trip, consider travel dates, flight options and activities at your destination. This page includes helpful information to help you compare flights and start planning your visit.
Explore local attractions, dining, entertainment and other experiences highlighted on this page to help plan your visit.
