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>

$207 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.

Round-trip

One-way

Last minute

Direct

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

KAYAK's recommended round-trip deals from the most popular airlines that fly from Ontario to St. Louis.

Discover the best prices for you by selecting your travel dates on KAYAK.

11:00 am - 8:10 pmYYZ-STL

34h 10m2 stops

12:15 pm - 7:37 pmSTL-YYZ

30h 22m2 stops

$391

Find Deal

Thu, May 22 - Sun, May 25

9:50 am - 11:37 pmYYZ-STL

14h 47m1 stop

9:50 am - 9:08 pmSTL-YYZ

10h 18m2 stops

$408

Find Deal

Tue, Jun 10 - Fri, Jun 13

11:30 am - 12:36 pmYYZ-STL

2h 06mnonstop

7:30 am - 10:25 amSTL-YYZ

1h 55mnonstop

$409Air Canada

Find Deal

Sat, Jun 14 - Sat, Jun 21

11:30 am - 12:36 pmYYZ-STL

2h 06mnonstop

1:30 pm - 9:44 pmSTL-YYZ

7h 14m1 stop

$411Air Canada

Find Deal

Sat, Jun 14 - Sat, Jun 21

1:25 pm - 6:01 pmYYZ-STL

5h 36m1 stop

6:00 am - 1:40 pmSTL-YYZ

6h 40m1 stop

$441Delta

Find Deal

Thu, May 22 - Tue, May 27

12:00 pm - 3:47 pmYYZ-STL

4h 47m1 stop

6:00 am - 1:47 pmSTL-YYZ

6h 47m1 stop

$442United Airlines

Find Deal

Fri, Aug 1 - Tue, Aug 5

7:20 am - 3:44 pmYYZ-STL

9h 24m2 stops

8:00 am - 1:24 pmSTL-YYZ

4h 24m1 stop

$456United Airlines

Find Deal

Thu, Sep 11 - Wed, Oct 29

6:00 am - 8:53 pmYUL-STL

15h 53m1 stop

6:00 am - 4:07 pmSTL-YUL

9h 07m1 stop

$465Delta

Find Deal

Fri, Jun 13 - Sun, Jun 15

6:30 am - 10:32 amYYZ-STL

5h 02m1 stop

6:40 am - 11:18 amSTL-YYZ

3h 38m1 stop

$493WestJet

Find Deal

Thu, Jun 19 - Sun, Jun 22

6:15 am - 11:31 amYYZ-STL

6h 16m1 stop

6:30 am - 6:04 pmSTL-YYZ

10h 34m2 stops

$510WestJet

Find Deal

Sat, Jun 14 - Sat, Jun 21

Useful Info

Low season	January
High season	December
Cheapest flight	$207

Best time to beat the crowds but there is an average 6% increase in price.

Most popular time to fly with an average 9% increase in price.

Flight from Montreal 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)

$207 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