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$ 284 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

Thu, 17 Dec - Thu, 31 Dec

1:20 p.m. - 10:32 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

10h 12m1 stop Chicago O'Hare Intl

6:00 a.m. - 2:44 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

7h 44m1 stop Chicago O'Hare Intl

C$ 478American Airlines

Fri, 11 Dec - Fri, 18 Dec

11:36 a.m. - 7:58 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

9h 22m1 stop Chicago O'Hare Intl

6:00 a.m. - 5:40 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

10h 40m1 stop Chicago O'Hare Intl

C$ 478American Airlines

Thu, 10 Dec - Tue, 15 Dec

1:40 p.m. - 10:57 a.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

22h 17m2 stops Austin Bergstrom Denver Intl

6:20 p.m. - 1:40 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

18h 20m1 stop Orlando

C$ 524Multiple Airlines

Thu, 10 Dec - Tue, 15 Dec

6:30 a.m. - 12:12 a.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

18h 42m1 stop Orlando

6:20 p.m. - 1:40 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

18h 20m1 stop Orlando

C$ 537Multiple Airlines

Wed, 16 Dec - Thu, 7 Jan

6:45 a.m. - 2:41 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

8h 56m1 stop Chicago O'Hare Intl

9:05 a.m. - 6:45 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

8h 40m1 stop Chicago O'Hare Intl

C$ 803United Airlines

Thu, 17 Dec - Thu, 7 Jan

8:05 a.m. - 6:18 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

11h 13m1 stop Chicago O'Hare Intl

8:15 a.m. - 4:47 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

7h 32m1 stop Chicago O'Hare Intl

C$ 803United Airlines

Thu, 17 Dec - Fri, 8 Jan

8:05 a.m. - 6:18 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

11h 13m1 stop Chicago O'Hare Intl

8:15 a.m. - 4:47 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

7h 32m1 stop Chicago O'Hare Intl

C$ 803United Airlines

Thu, 19 Nov - Sun, 22 Nov

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 903Air Canada

Tue, 29 Dec - Mon, 4 Jan

10:05 a.m. - 3:26 p.m.YOW Ottawa-STL Lambert-St Louis

6h 21m1 stop Toronto Pearson Intl

4:05 p.m. - 10:55 p.m.STL Lambert-St Louis-YOW Ottawa

5h 50m1 stop Toronto Pearson Intl

C$ 919Air Canada

Tue, 1 Dec - Tue, 8 Dec

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 922Air Canada

Recent last minute flight deals from Ontario to St. Louis

Mon, 2 Nov - Mon, 9 Nov

1:00 p.m. - 1:31 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

25h 31m2 stops Nashville Intl Jonesboro

4:26 p.m. - 3:18 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

21h 52m1 stop Orlando

C$ 776Multiple Airlines

Sun, 1 Nov - Mon, 9 Nov

1:00 p.m. - 1:31 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

25h 31m2 stops Nashville Intl Jonesboro

4:26 p.m. - 3:18 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

21h 52m1 stop Orlando

C$ 776Multiple Airlines

Thu, 5 Nov - Mon, 9 Nov

8:30 p.m. - 12:33 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

17h 03m1 stop Las Vegas Harry Reid Intl

6:34 p.m. - 9:52 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

26h 18m2 stops Atlanta Hartsfield-Jackson Austin Bergstrom

C$ 785Multiple Airlines

Tue, 3 Nov - Mon, 9 Nov

6:25 p.m. - 5:40 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

24h 15m2 stops New York LaGuardia Atlanta Hartsfield-Jackson

4:26 p.m. - 3:18 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

21h 52m1 stop Orlando

C$ 796Multiple Airlines

Thu, 5 Nov - Sun, 15 Nov

6:15 a.m. - 2:34 p.m.YOW Ottawa-STL Lambert-St Louis

9h 19m1 stop Chicago O'Hare Intl

4:05 p.m. - 1:40 a.m.STL Lambert-St Louis-YOW Ottawa

8h 35m1 stop Toronto Pearson Intl

C$ 1,192Air Canada

Wed, 4 Nov - Tue, 10 Nov

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 6:59 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,193Air Canada

Wed, 4 Nov - Wed, 11 Nov

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 6:59 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,213Air Canada

Wed, 4 Nov - Wed, 11 Nov

10:30 a.m. - 4:17 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

6h 47m1 stop Newark

4:05 p.m. - 6:59 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,224United Airlines

Wed, 4 Nov - Tue, 10 Nov

10:30 a.m. - 4:17 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

6h 47m1 stop Newark

8:00 a.m. - 4:37 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

7h 37m2 stops Washington, D.C. Dulles Intl New York LaGuardia

C$ 1,232United Airlines

Wed, 4 Nov - Mon, 9 Nov

7:43 a.m. - 9:52 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

15h 09m1 stop Newark

1:00 p.m. - 10:18 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

8h 18m1 stop Washington, D.C. Dulles Intl

C$ 1,243United Airlines

Recent direct flight deals from Ontario to St. Louis

Thu, 19 Nov - Sun, 22 Nov

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 903Air Canada

Tue, 1 Dec - Tue, 8 Dec

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 922Air Canada

Tue, 8 Dec - Sat, 12 Dec

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 922Air Canada

Sun, 22 Nov - Mon, 30 Nov

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 922Air Canada

Thu, 17 Dec - Sat, 2 Jan

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 1,336United Airlines

Tue, 15 Dec - Sat, 2 Jan

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 1,336United Airlines

Fri, 18 Dec - Sat, 2 Jan

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 1,336United Airlines

Sun, 20 Dec - Sat, 2 Jan

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 1,336United Airlines

Sun, 29 Nov - Sat, 5 Dec

2:10 p.m. - 3:26 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 16mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 1,510Multiple Airlines

Tue, 10 Nov - Fri, 13 Nov

2:10 p.m. - 3:23 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 13mdirect

4:05 p.m. - 7:05 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

2h 00mdirect

C$ 1,972Multiple Airlines

Useful Info

Low season	April
High season	October
Cheapest flight	C$ 284

Best time to beat the crowds but there is an average 21% increase in price.

Most popular time to fly (14% more expensive 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.