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.

C$ 261 CHEAP FLIGHTS from Ontario to St. Louis

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Flight Deals

Cheap Flights from Ontario to St. Louis

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, 17 Oct - Mon, 26 Oct

7:29 a.m. - 4:43 p.m.

YYZ

STL

10h 14m

1 stop

5:00 a.m. - 2:33 p.m.

STL

YYZ

8h 33m

1 stop

C$ 439American Airlines

Wed, 9 Sep - Sat, 19 Sep

6:30 a.m. - 1:16 p.m.

YYZ

STL

7h 46m

1 stop

7:27 a.m. - 5:44 p.m.

STL

YYZ

9h 17m

1 stop

C$ 454American Airlines

Mon, 14 Sep - Mon, 21 Sep

6:30 a.m. - 4:48 p.m.

YYZ

STL

11h 18m

1 stop

7:21 a.m. - 6:35 p.m.

STL

YYZ

10h 14m

1 stop

C$ 454American Airlines

Sun, 8 Nov - Mon, 9 Nov

6:30 a.m. - 7:39 p.m.

YYZ

STL

14h 09m

1 stop

10:35 a.m. - 5:40 p.m.

STL

YYZ

30h 05m

2 stops

C$ 472Multiple Airlines

Sun, 8 Nov - Mon, 9 Nov

6:30 a.m. - 7:39 p.m.

YYZ

STL

14h 09m

1 stop

8:34 p.m. - 12:10 a.m.

STL

YYZ

26h 36m

1 stop

C$ 517Multiple Airlines

Mon, 14 Sep - Mon, 21 Sep

9:50 a.m. - 4:34 p.m.

YYZ

STL

7h 44m

1 stop

2:29 p.m. - 2:30 p.m.

STL

YYZ

47h 01m

2 stops

C$ 541Multiple Airlines

Fri, 21 Aug - Sun, 23 Aug

7:15 p.m. - 8:24 p.m.

YYZ

STL

2h 09mdirect

8:55 a.m. - 11:56 a.m.

STL

YYZ

2h 01mdirect

C$ 608Air Canada

Sat, 22 Aug - Fri, 28 Aug

10:00 a.m. - 2:04 p.m.

YOW

STL

5h 04m

1 stop

8:55 a.m. - 3:10 p.m.

STL

YOW

5h 15m

1 stop

C$ 645Air Canada

Tue, 1 Dec - Wed, 2 Dec

4:36 p.m. - 9:13 p.m.

YOW

STL

5h 37m

1 stop

7:33 a.m. - 7:27 p.m.

STL

YOW

10h 54m

2 stops

C$ 655United Airlines

Sat, 12 Sep - Sat, 19 Sep

6:00 a.m. - 2:15 p.m.

YOW

STL

9h 15m

2 stops

1:36 p.m. - 11:54 p.m.

STL

YOW

9h 18m

2 stops

C$ 655United Airlines

Useful Info

Low season	April
High season	August
Cheapest flight	C$ 261

Best time to beat the crowds but there is an average 26% increase in price.

Most popular time to fly and prices are also 7% lower on average.

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.

Chesterfield

St. Charles

Fairview Heights

Maryland Heights

O'Fallon

Clayton

Wentzville

Edwardsville

Alton

Farmington

Collinsville

Shrewsbury

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

Airports

Cabin class

Complete your trip

Flights to other cities

Origins

Other airports

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

St. Louis (STL)

STL

C$ 261 Find Cheap Flights from Ontario to St. Louis – Compare and Save

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

Low season

High season

Cheapest flight

FAQs for booking flights from Ontario to St. Louis

Travelling 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

Flights to other popular destinations

Flights from domestic origins to St. Louis

Choose which airport to fly into in St. Louis