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Flights from St. Louis to Ontario

Cheap flight deals from St. Louis to Ontario

We've found these cheap flights for you. You can book one-way or round-trip flight tickets.

  • Round-trip
  • One way

Crossed out prices are calculated based on the average price of the corresponding route on Trip.com.

When is the cheapest time to fly from St. Louis to Ontario?

We monitor flight fares to help you find the best deals effortlessly

Cheapest flights
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  • 6 13
  • 13 20
  • 20 27

  • May

    27 4
  • 4 11
  • 11 18
  • 18 25

  • Jun

    25 1
  • 1 8
  • 8 15
  • 15 22
  • 22 29
Displayed prices are calculated based on the cheapest average weekly prices of the corresponding route on Trip.com.

Frequently Asked Questions

  • When are flight tickets from St. Louis (STL) to Ontario (ONT) the cheapest?

    Airlines adjust prices for flights from St. Louis to Ontario based on the date and time of your booking. By analyzing data from all airlines, on Trip.com, you can find the lowest flight prices on Tuesdays, Wednesdays, and Saturdays.

  • How much do flights from St. Louis (STL) to Ontario (ONT) cost?

    According to Trip.com's data, the lowest price is around AED 1,288.

  • What's the most popular airline for non-stop flights from St. Louis (STL) to Ontario (ONT)?

    Southwest Airlines operates 1 non-stop flights from St. Louis (STL) to Ontario (ONT).

How to find a cheap flight from St. Louis to Ontario

Wait until the last minute and flight costs are often sky-high. Plan ahead, book the right way, and your savings can soar. We have loads of saving tips to help you find a cheap flight from St. Louis to Ontario. Book your flights at the right time and save more.
1
Being flexible with your dates to get the cheapest St. Louis to Ontario ticket.
Tap "Date" on flight search bar to scan through the calender for St. Louis to Ontario airfare over next 6 months in 2025. If you would like to fly in next 3 months, it seems the cheapest date is on Sat, May 3 at AED 206 for one-way flights.
2
Compare cheap St. Louis to Ontario flight deals from over hundreds of airlines.
Our extensive search allows you to compare prices from over 500 airlines to choose the cheapest flight tickets from St. Louis to Ontario. The cheapest airline operating is Frontier Airlines.
3
Set up a Price Alert
By setting up a Price Alert for your St. Louis to Ontario route, you can easily track the price of your airline tickets from without manually checking every day.
4
Don't miss cheap St. Louis to Ontario flight deals and promo codes.
You can always get the latest deals through Trip.com Deals and Promo Codes for cheap flights. If registering a free membership, you can receive more deals for your flights.
5
Book early or wait unitl the last minute.
It's always better to book early. Flight tickets tend to be the cheapest when they are first released, normally about a year before the departure date. So, check online as soon as the flights you want become available. If you miss the cheapest time, you can still find lower-priced tickets as the flight date approaches.
6
Search for flights on the go.
To get the best flight booking experience on the go, download Trip.com and search for cheap flight tickets from St. Louis to Ontario to get exclusive deals for you.

Flight Info | St. Louis to Ontario

Cheapest one-way flight price AED 206
Cheapest return ticket price AED 885
Off-season for travel October
Peak season for travel November
Flight distance 10,023.47 km
Popular airline Delta Air Lines

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