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>

C$ 298 CHEAP FLIGHTS from Ontario to St. Louis

STL

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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, 9 Jul - Wed, 15 Jul

3:10 p.m. - 6:42 p.m.

YOW

STL

4h 32m

1 stop

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

STL

YOW

5h 15m

1 stop

C$ 527Air Canada

Tue, 18 Aug - Sat, 7 Nov

2:35 p.m. - 6:42 p.m.

YOW

STL

5h 07m

1 stop

4:15 p.m. - 11:48 p.m.

STL

YOW

6h 33m

1 stop

C$ 534Air Canada

Tue, 18 Aug - Sat, 7 Nov

6:05 a.m. - 3:38 p.m.

YOW

STL

10h 33m

2 stops

9:23 a.m. - 9:34 p.m.

STL

YOW

11h 11m

1 stop

C$ 535United Airlines

Mon, 27 Jul - Mon, 3 Aug

5:50 p.m. - 11:44 p.m.

YOW

STL

6h 54m

1 stop

4:53 p.m. - 9:11 a.m.

STL

YOW

15h 18m

1 stop

C$ 545United Airlines

Fri, 3 Jul - Tue, 7 Jul

6:00 a.m. - 3:46 p.m.

YOW

STL

10h 46m

2 stops

1:13 p.m. - 10:05 p.m.

STL

YOW

7h 52m

2 stops

C$ 546United Airlines

Thu, 16 Jul - Tue, 21 Jul

2:50 p.m. - 6:15 p.m.

YYZ

STL

28h 25m

2 stops

7:03 p.m. - 6:39 a.m.

STL

YYZ

10h 36m

1 stop

C$ 584Multiple Airlines

Mon, 3 Aug - Mon, 10 Aug

10:50 a.m. - 6:05 p.m.

YYZ

STL

32h 15m

2 stops

7:10 p.m. - 5:09 p.m.

STL

YYZ

20h 59m

1 stop

C$ 585Multiple Airlines

Tue, 18 Aug - Sat, 7 Nov

5:34 p.m. - 8:23 a.m.

YUL

STL

15h 49m

1 stop

6:00 a.m. - 3:11 p.m.

STL

YUL

8h 11m

1 stop

C$ 645American Airlines

Wed, 4 Nov - Sat, 7 Nov

9:28 a.m. - 8:51 p.m.

YUL

STL

12h 23m

1 stop

6:00 a.m. - 1:36 p.m.

STL

YUL

6h 36m

1 stop

C$ 683Delta

Thu, 15 Oct - Mon, 19 Oct

7:00 a.m. - 12:56 p.m.

YUL

STL

6h 56m

1 stop

7:20 a.m. - 5:03 p.m.

STL

YUL

8h 43m

1 stop

C$ 686Delta

Useful Info

Low season	April
High season	August
Cheapest flight	C$ 298

Best time to beat the crowds but there is an average 29% increase in price.

Most popular time to fly and prices are also 2% 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

Collinsville

St. Charles

Maryland Heights

Fairview Heights

O'Fallon

Clayton

Eureka

Farmington

Glencoe

Wentzville

Edwardsville

Alton

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$ 298 Find Cheap Flights from Ontario to St. Louis – Compare and Save

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

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