CA $238 Cheap Flights from St. Louis (STL) to Ontario (ONT)

The easy way to book your flights from St. Louis to Ontario 

With Expedia, it’s simple to find and book flights to Ontario from St. Louis whether you’re traveling for business or pleasure. Enter your travel dates, hit search, and choose your flight from 20 airlines that cover this route. There are nonstop flights to Los Angeles - Ontario Intl., too.  

Choose your preferred carrier and cabin class with the advanced search tool and select your ideal departure time. Then, if you want, you can see just nonstop or refundable flights. And if you’re traveling last minute, just enter the date to check out flights from St. Louis to Ontario today, tomorrow, or this week.  

Save dollars with cheap flights from Lambert-St. Louis Intl., STL to Los Angeles - Ontario Intl., ONT 

Sort your search results by price to find great deals on your flight from St. Louis to Ontario—you get all your cheapest options first. Grab yourself a bargain now—the lowest price on flights to Ontario from St. Louis currently is just CA $424 rising to CA $543.  

Here are more money-saving tips: 

• Fly in May when flight prices are normally at their lowest 
• Book about a month to 6 weeks before you travel for the best prices to Ontario  
• Avoid peak season and weekends when flights can cost more
• Early morning and late-night flights are sometimes cheaper, so try varying your travel times 
• One surefire way to save money on your flight is to book your flight and hotel together with Expedia. Sometimes, the savings are so large that the flight is basically free! 

Reasons to choose Expedia for your flight to Ontario from St. Louis 

Whatever your destination, budget, or reason to travel, in just one quick search, you can choose from loads of flights, airlines, and cabin classes. The filters make it quick and easy to find your ideal flights, and if you choose one of the flexible options, you won’t be charged to change your flight. So book your flight to Ontario with Expedia today.