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>

$146 CHEAP FLIGHTS from Ontario to St. Louis

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

...and more

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41,299,237 searches in the past 7 days on KAYAK

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Filter your dealsChoose cabin class, free Wi-Fi and more.

Cheapest round-trip

$242

Overall average: $679

Multiple Airlines

Fri 1/23Sun 1/25

YOW - STL • 1 stop

Cheapest non-stop

$363

Typical prices: $418-$1,040

Air Canada

Fri 11/21Mon 11/24

YYZ - STL • Non-stop

Start a new search

KAYAK searches 100s of sites at once to find you the best travel deals.

We hope you love your trip to St. Louis!

Flight 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.

Round-trip

One-way

Last minute

Direct

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

Fri, Jan 23 - Sun, Jan 25

9:30 am - 10:33 pmYOW-STL

14h 03m1 stop

5:11 pm - 5:13 pmSTL-YOW

23h 02m1 stop

$242Multiple Airlines

Find Deal

Tue, Feb 3 - Wed, Feb 4

9:15 am - 3:29 pmYOW-STL

7h 14m1 stop

4:05 pm - 11:08 pmSTL-YOW

6h 03m1 stop

$296Air Canada

Find Deal

Fri, Jan 23 - Sun, Jan 25

5:11 pm - 10:58 pmYOW-STL

6h 47m1 stop

9:57 am - 11:54 pmSTL-YOW

12h 57m2 stops

$301United Airlines

Find Deal

Tue, Apr 7 - Wed, Apr 8

6:52 am - 12:20 pmYOW-STL

6h 28m1 stop

6:30 am - 12:41 pmSTL-YOW

5h 11m1 stop

$302United Airlines

Find Deal

Wed, Jan 21 - Sat, Jan 24

11:30 am - 6:14 pmYYZ-STL

7h 44m1 stop

6:43 pm - 10:53 amSTL-YYZ

15h 10m1 stop

$303American Airlines

Find Deal

Tue, Dec 9 - Wed, Dec 10

11:36 am - 8:24 pmYYZ-STL

9h 48m1 stop

5:05 am - 4:03 pmSTL-YYZ

9h 58m1 stop

$306American Airlines

Find Deal

Sat, Dec 20 - Mon, Jan 5

3:10 pm - 11:33 pmYOW-STL

9h 23m1 stop

4:05 pm - 11:08 pmSTL-YOW

6h 03m1 stop

$307Multiple Airlines

Find Deal

Fri, Dec 5 - Mon, Dec 8

6:00 am - 1:14 pmYYZ-STL

8h 14m1 stop

5:15 am - 4:03 pmSTL-YYZ

9h 48m1 stop

$320American Airlines

Find Deal

Tue, Nov 25 - Fri, Nov 28

12:08 pm - 5:09 pmYYZ-STL

6h 01m1 stop

6:40 am - 11:24 amSTL-YYZ

3h 44m1 stop

$385Delta

Find Deal

Mon, Mar 23 - Thu, Mar 26

5:10 pm - 11:10 pmYYZ-STL

7h 00m1 stop

6:45 am - 11:34 amSTL-YYZ

3h 49m1 stop

$445Delta

Find Deal

Useful Info

Low season	June
High season	December
Cheapest flight	$146

Best time to beat the crowds with an average 10% drop in price.

Most popular time to fly with an average 13% 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.

O'Fallon

Wentzville

Farmington

Eureka

Litchfield

Grafton

Shrewsbury

Glencoe

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)

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$146 Find Cheap Flights from Ontario to St. Louis

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

Everything you should know

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.

Traveling to a place near St. Louis?

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