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. Visit our flight page for the latest deals!>/a>

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. Visit our flight page for the latest deals!>/a>

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. Visit our flight page for the latest deals!>/a>

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. Visit our flight page for the latest deals!>/a>

$174 CHEAP FLIGHTS from Ontario to St. Louis

KAYAK searches hundreds of travel sites at once for deals on flights to St. Louis

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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.

Round-trip

One-way

Last minute

Direct

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

Sat, Nov 8 - Sat, Nov 15

4:44 pm - 11:56 pmYYZ-STL

8h 12m1 stop

6:00 am - 4:04 pmSTL-YYZ

9h 04m1 stop

$321American Airlines

Find Deal

Sat, Sep 13 - Sat, Sep 20

12:31 pm - 9:53 pmYUL-STL

10h 22m1 stop

2:01 pm - 11:46 amSTL-YUL

20h 45m1 stop

$326American Airlines

Find Deal

Fri, Sep 12 - Sun, Sep 14

2:15 pm - 3:18 pmYYZ-STL

2h 03mnonstop

4:05 pm - 7:00 pmSTL-YYZ

1h 55mnonstop

$352Air Canada

Find Deal

Fri, Sep 12 - Sun, Sep 14

2:15 pm - 3:18 pmYYZ-STL

2h 03mnonstop

1:30 pm - 9:39 pmSTL-YYZ

7h 09m1 stop

$357Air Canada

Find Deal

Mon, Sep 8 - Thu, Sep 11

6:04 am - 4:49 pmYYZ-STL

11h 45m1 stop

6:05 am - 4:08 pmSTL-YYZ

9h 03m1 stop

$407Delta

Find Deal

Mon, Sep 8 - Tue, Sep 16

6:00 am - 8:06 amYUL-STL

27h 06m1 stop

6:40 am - 12:00 pmSTL-YUL

4h 20m1 stop

$408Delta

Find Deal

Sun, Sep 7 - Thu, Sep 11

6:45 am - 11:59 pmYYZ-STL

18h 14m2 stops

10:35 am - 8:55 pmSTL-YYZ

9h 20m1 stop

$417

Find Deal

Sun, Sep 7 - Thu, Sep 11

6:45 am - 11:59 pmYYZ-STL

18h 14m2 stops

10:35 am - 8:55 pmSTL-YYZ

9h 20m1 stop

$431

Find Deal

Wed, Aug 27 - Wed, Sep 3

6:15 am - 3:44 pmYUL-STL

10h 29m1 stop

7:04 pm - 10:40 amSTL-YUL

14h 36m1 stop

$445United Airlines

Find Deal

Tue, Aug 26 - Tue, Sep 2

12:45 pm - 9:32 pmYYZ-STL

9h 47m2 stops

7:04 pm - 9:58 amSTL-YYZ

13h 54m1 stop

$458United Airlines

Find Deal

Useful Info

Low season	June
High season	December
Cheapest flight	$174

Best time to beat the crowds with an average 12% drop in price.

Most popular time to fly with an average 10% increase in price.

Flight from Toronto 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

Airports

Cabin class

Complete your trip

Direct Flights

Flights to other cities

Origins

Other airports

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

St. Louis (STL)

Not what you’re looking for? Find thousands of other hotels, flights, car rentals and package deals with KAYAK.

$174 Find Cheap Flights from Ontario to St. Louis

KAYAK searches hundreds of travel sites at once for deals on flights to St. Louis

Cheap Flights from Ontario to St. Louis

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

Recent one-way flight deals from Ontario to St. Louis

Recent last minute flight deals from Ontario to St. Louis

Recent direct flight deals from Ontario to St. Louis

Good to know

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

Cabin class types available on flights to Ontario

Complete your trip to St. Louis with a hotel stay or car rental

Find direct flights for St. Louis

Flights to other popular destinations

Flights from domestic origins to St. Louis

Choose which airport to fly into in St. Louis