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

Popular airlines from Los Angeles - Ontario Intl. Airport (ONT) to St. Louis Lambert Intl. Airport (STL)

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Frequently asked questions

Is it cheaper to buy a plane ticket from Los Angeles - Ontario Intl. Airport (ONT) to Lambert-St. Louis Intl. Airport (STL) last minute?
When it comes to booking your flights, it pays to be prepared. While you may be able to find a deal on an ONT to Lambert-St. Louis Intl. Airport (STL) flight at the last minute, fares usually don't get cheaper as the date of departure nears. Based on flight pricing and demand studies in 2022, we have found that the sweet spot to book a domestic flight is between 28 – 35 days ahead. For international trips it's between three and four months.
What airports do you fly into for St. Louis from Ontario?
Lambert-St. Louis Intl. Airport (STL), Spirit of St. Louis Airport (SUS) and St. Louis Downtown Airport (CPS) are your choices when jetting from Ontario to St. Louis. Roughly 19 kilometers northwest of the center of St. Louis, Lambert-St. Louis Intl. Airport (STL) is the city's principal hub. Consider factors like flight departure and arrival times and the distance to your hotel before choosing your airport. Busch Stadium and Gateway Arch are a couple of leading attractions to add to your must-see list when you get to your destination.
Can I change the date of my flight from ONT to Lambert-St. Louis Intl. Airport (STL)?
Easily make changes to your ONT to STL trip by logging in to the Expedia Trips portal. But before you begin, read over the rules and conditions in your itinerary to see what you're able to do and whether fees apply. Some airlines have a change fee per person, plus any difference in fare prices. However, if you booked in the last 24 hours, you may be able to cancel for free and book new flights. You can also find your way to our Customer Service portal to find the answers to your questions and to connect with our Virtual Agent.

Travel information

Travel information

Origin airport
Los Angeles - Ontario Intl.
Destination airport
Lambert-St. Louis Intl.
Distance
2467 km

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