$156 Find Cheap Flights from Ontario to St. Louis

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight to St. Louis departing on 7/29. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

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Flights Deals

Cheap Flights from Ontario to St. Louis

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to St. Louis that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Ontario to St. Louis

Tue, Sep 2 - Thu, Sep 4
American Airlines Logo
6:30 am - 12:54 pmYYZ-STL
7h 24m1 stop
American Airlines Logo
5:55 am - 2:31 pmSTL-YYZ
7h 36m1 stop
$317American Airlines
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Wed, Sep 24 - Mon, Sep 29
American Airlines Logo
12:30 pm - 8:32 pmYUL-STL
9h 02m1 stop
American Airlines Logo
7:23 am - 4:30 pmSTL-YUL
8h 07m1 stop
$324American Airlines
Find Deal
Sat, Jun 28 - Wed, Jul 16
Air Canada Logo
11:30 am - 12:36 pmYYZ-STL
2h 06mnonstop
Air Canada Logo
9:15 am - 12:15 pmSTL-YYZ
2h 00mnonstop
$350Air Canada
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Sun, Jun 29 - Wed, Jul 16
Air Canada Logo
4:00 pm - 8:48 pmYYZ-STL
5h 48m1 stop
Air Canada Logo
9:15 am - 12:15 pmSTL-YYZ
2h 00mnonstop
$355Air Canada
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Mon, Jul 21 - Thu, Jul 24
 Logo
1:30 pm - 4:31 pmYYZ-STL
28h 01m1 stop
 Logo
9:50 am - 9:08 pmSTL-YYZ
10h 18m2 stops
Mon, Jul 21 - Fri, Jul 25
 Logo
1:30 pm - 4:31 pmYYZ-STL
28h 01m1 stop
 Logo
9:50 am - 9:08 pmSTL-YYZ
10h 18m2 stops
Mon, Jul 21 - Fri, Jul 25
Delta Logo
6:15 am - 11:34 amYYZ-STL
6h 19m1 stop
Delta Logo
3:41 pm - 9:59 pmSTL-YYZ
5h 18m1 stop
$416Delta
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Wed, Jul 16 - Sun, Jul 20
United Airlines Logo
9:00 am - 12:27 pmYYZ-STL
4h 27m1 stop
United Airlines Logo
6:33 am - 11:49 amSTL-YYZ
4h 16m1 stop
$424United Airlines
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Tue, Jul 1 - Thu, Jul 10
Delta Logo
6:15 am - 8:53 pmYYZ-STL
15h 38m1 stop
Delta Logo
1:29 pm - 11:59 pmSTL-YYZ
9h 30m1 stop
$435Delta
Find Deal
Sat, Jun 28 - Thu, Jul 10
United Airlines Logo
11:30 am - 12:36 pmYYZ-STL
2h 06mnonstop
United Airlines Logo
8:00 am - 3:46 pmSTL-YYZ
6h 46m1 stop
$449United Airlines
Find Deal
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Good to know

Low seasonJune
High seasonDecember
Cheapest flight$156
Best time to beat the crowds with an average 11% drop in price.
Most popular time to fly with an average 10% increase in price.
Flight from Toronto to St. Louis

FAQs for booking flights from Ontario to St. Louis

  • How does KAYAK find such low prices on flights from Ontario to St. Louis?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to St. Louis.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to St. Louis?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to St. Louis?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Louis with an airline and back to Ontario with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to St. Louis?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Louis from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Everything you need to know for your flight to St. Louis

Information on the airport you'll fly into in St. Louis

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