American Airlines offers flights from Ontario to Saint Louis. Browse available flight options and fares between LA/Ontario International Airport (ONT) and Lambert-St Louis Int'l Airport (STL) for business trips, family visits and short getaways.
Compare fares and schedules and choose the option that fits your trip to Saint Louis (STL). Prices and availability may change based on travel dates and demand.
Ontario (ONT)to
Round trip
Economy
Ontario (ONT)to
Round trip
Economy
Ontario (ONT)to
Round trip
Economy
Ontario (ONT)to
Round trip
Economy
Ontario (ONT)to
Round trip
Economy
Ontario (ONT)to
Round trip
Economy
Ontario (ONT)to
Round trip
Economy
Ontario (ONT)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 Saint Louis.
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 St. Louis Lambert International Airport (STL), located about 14 miles northwest of downtown St. Louis. The airport offers convenient access to the city and the greater St. Louis area.
Getting from the airport
Several ground transportation options are available between St. Louis Lambert International Airport (STL) and downtown St. Louis. Options vary by travel time, cost and convenience, allowing travelers to choose what best fits their plans.
For the most up-to-date transportation information, visit St. Louis Lambert International Airport’s official website.
The MetroLink light rail connects STL with downtown St. Louis, with travel times of about 30 minutes.
Some hotels provide shuttle service between STL and their properties. Travelers should confirm shuttle schedules and pickup locations with their hotel.
Taxis and app-based rideshare services are available at designated pickup areas outside airport terminals.
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.
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