Cheap flights from St. Louis to Ontario

Choose between WN, American Airlines, or Frontier Airlines to find the best price

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Travelers usually depart from St. Louis Lambert International, or St. Louis Union Station when they travel from St. Louis to Ontario. Book your trip to arrive at Ontario International, Ontario, CA station, Montclair (Ontario), or Ontario Bus Stop. The most popular airlines for this route are WN, American Airlines, Frontier Airlines, United Airlines, and Delta Air Lines. St. Louis and Ontario have 171 direct flights per week.

Weekly flights

MondaysTuesdaysWednesdaysThursdaysFridaysSaturdaysSundays
Number of flights21203141-2434

Check-in for a flight from St. Louis to Ontario

NameCarrier codeIATA CodePassport needed during bookingAirport check-in closesOnline check-in available
WNSWAWNNoUnknownNo
American AirlinesAALAAYesUnknownNo
Frontier AirlinesFFTF9NoUnknownNo
United AirlinesUALUAYesUnknownNo
Delta Air LinesDALDLYesUnknownNo

Frequently asked questions

What are the most popular routes to and from St. Louis?

Travelers frequently search for route combinations, such as St. Louis and Denver International, Phoenix Sky Harbor International, O Hare International, Ontario International, Owensboro–Daviess County Regional, Quincy Regional, Jonesboro Municipal, Waynesville-St. Robert Regional, Williamson County Regional, McKellar–Sipes Regional, Kirksville Regional.

What are the most popular routes to and from Ontario?

Travelers frequently search for route combinations, such as Ontario and Orlando International, McCarran International, Denver International, Phoenix Sky Harbor International, San Diego International, Philadelphia International, Detroit Metropolitan, Cincinnati/Northern Kentucky International, St. Louis Lambert International, Colorado Springs, Eppley Airfield.

What buses and trains depart from St. Louis?

A number of bus and train companies depart from St. Louis, including Greyhound, Burlington Trailways.

Is it possible to combine flights, buses, and trains in one itinerary when traveling between St. Louis and Ontario?

What is Virtual Interlining and how do I use it?

Which airlines fly between St. Louis and Ontario?

When's the best time to travel between St. Louis and Ontario?

What flights operate between St. Louis and Ontario?

Is it possible to reach St. Louis by bus or train?

What time do nonstop (direct) flights between St. Louis and Ontario depart?

What time do nonstop (direct) flights between St. Louis and Ontario arrive?

What time do flights between St. Louis and Ontario depart?

What time do flights between St. Louis and Ontario arrive?

Planning a trip? Thanks to our Virtual Interlining algorithm, we offer billions of route combinations between any A and any B in the world by plane, train, and bus. Find the cheapest routes and best deals for you, as well as the best dates on which to travel.

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