How many flights depart from Region of Ontario to St. Louis on average per day?

2 flights are operational daily from Region of Ontario to St. Louis as of December 2025. The most popular departure time for this route is 2:00p.m., with 100% of flights per day taking off in the afternoon.

Which airlines fly to St. Louis?

Air Canada, United Airlines and WestJet are the top three most popular airlines that fly to St. Louis from Region of Ontario according to our data. Air Canada is the first choice among our users, with 71% of people opting to fly with this airline when travelling to St. Louis. Keep in mind that there are 5 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.

How long does it take to fly to St. Louis?

Flight times vary depending on what airport in Region of Ontario you fly out of and what airport in St. Louis you fly into. For example, flying from Toronto to St. Louis takes 2h 06m on average. On the other hand, flying from Ottawa to St. Louis takes 7h 04m on average. Keep in mind that it’s always quicker to opt for a non-stop flight, so be sure to check momondo to see if there are any available for your route.

How many flights depart from Region of Ontario to St. Louis on average per week?

The number of flights available between Region of Ontario and St. Louis is 14 per week as of December 2025. The most frequent departure day is Mon, with 14% of weekly flights leaving on this day.

What is the cheapest airline that flies from Ontario to Lambert-St Louis?

Air Canada, United Airlines, and Delta are the most popular carriers operating from Ontario to Lambert-St Louis

When did momondo last update prices for flights from Ontario to Lambert-St Louis Airport?

Prices for flights from Ontario to Lambert-St Louis Airport are refreshed on a daily basis.

How many operators does momondo search for flights from Ontario to Lambert-St Louis Airport?

The number of operators available for flights from Ontario to Lambert-St Louis Airport is 5 as of December 2025.

How old do you have to be to fly from Ontario to Lambert-St Louis Airport?

The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario to Lambert-St Louis Airport.

What documentation or ID do you need to fly to Lambert-St Louis Airport?

The travel and health documents you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

C$ 184 Cheap Flights from Ontario to St. Louis in 2025/26

1 adult

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Find the cheapest flights from Ontario to St. Louis

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

Enter your travel dates to find the best prices.

3:40 p.m. - 11:33 p.m.

YYZ

STL

32h 53m2 stops

5:42 p.m. - 2:08 p.m.

STL

YYZ

19h 26m1 stop

C$ 388Multiple Airlines

Tue, 27 Jan - Mon, 2 Feb

7:10 a.m. - 10:33 p.m.

YYZ

STL

16h 23m1 stop

5:11 p.m. - 12:11 a.m.

STL

YYZ

30h 00m1 stop

C$ 392Multiple Airlines

Mon, 12 Jan - Wed, 14 Jan

7:15 a.m. - 10:34 p.m.

YYZ

STL

16h 19m1 stop

5:11 p.m. - 2:20 p.m.

STL

YYZ

20h 09m1 stop

C$ 397Multiple Airlines

Tue, 13 Jan - Fri, 16 Jan

7:15 a.m. - 10:34 p.m.

YYZ

STL

16h 19m1 stop

8:32 p.m. - 2:20 p.m.

STL

YYZ

16h 48m2 stops

C$ 410Multiple Airlines

Tue, 13 Jan - Fri, 16 Jan

5:20 p.m. - 9:08 p.m.

YOW

STL

4h 48m1 stop

7:45 a.m. - 1:59 p.m.

STL

YOW

5h 14m1 stop

C$ 425United Airlines

Thu, 9 Apr - Sat, 11 Apr

5:55 p.m. - 11:59 p.m.

YOW

STL

7h 04m1 stop

8:30 a.m. - 2:27 p.m.

STL

YOW

4h 57m1 stop

C$ 428United Airlines

Wed, 21 Jan - Sat, 24 Jan

11:30 a.m. - 9:15 p.m.

YYZ

STL

10h 45m1 stop

6:00 a.m. - 4:03 p.m.

STL

YYZ

9h 03m1 stop

C$ 439American Airlines

Tue, 3 Feb - Wed, 4 Feb

3:50 p.m. - 10:20 a.m.

YUL

STL

19h 30m1 stop

6:33 p.m. - 3:05 p.m.

STL

YUL

19h 32m1 stop

C$ 577American Airlines

Sun, 8 Feb - Sun, 15 Feb

5:40 a.m. - 4:37 p.m.

YOW

STL

11h 57m2 stops

10:19 a.m. - 12:42 a.m.

STL

YOW

13h 23m2 stops

C$ 781Delta

Mon, 19 Jan - Sat, 24 Jan

5:40 a.m. - 4:37 p.m.

YOW

STL

11h 57m2 stops

10:19 a.m. - 12:42 a.m.

STL

YOW

13h 23m2 stops

C$ 790Delta

Mon, 19 Jan - Sat, 24 Jan

United Airlines flights from Region of Ontario to St. Louis

Our best United Airlines deals on Region of Ontario to St. Louis flight tickets

United Airlines

9 Apr

YOW5:20 p.m.Ottawa

4h 48m

1 stop

STL9:08 p.m.Lambert-St Louis

11 Apr

STL7:45 a.m.Lambert-St Louis

5h 14m

1 stop

YOW1:59 p.m.Ottawa

C$ 425

Find similar

United Airlines

21 Jan

YOW5:55 p.m.Ottawa

7h 04m

1 stop

STL11:59 p.m.Lambert-St Louis

24 Jan

STL8:30 a.m.Lambert-St Louis

4h 57m

1 stop

YOW2:27 p.m.Ottawa

C$ 428

Find similar

United Airlines

21 Jan

YOW5:11 p.m.Ottawa

6h 47m

1 stop

STL10:58 p.m.Lambert-St Louis

24 Jan

STL9:57 a.m.Lambert-St Louis

10h 59m

2 stops

YOW9:56 p.m.Ottawa

C$ 441

Find similar

Air Canada flights from Region of Ontario to St. Louis

Our best Air Canada deals on Region of Ontario to St. Louis flight tickets

Air Canada

6 Mar

YYZ2:00 p.m.Toronto Pearson Intl

2h 29m

STL3:29 p.m.Lambert-St Louis

8 Mar

STL4:05 p.m.Lambert-St Louis

2h 01m

YYZ7:06 p.m.Toronto Pearson Intl

C$ 527

Find similar

Air Canada

22 Jan

YYZ2:00 p.m.Toronto Pearson Intl

2h 29m

STL3:29 p.m.Lambert-St Louis

26 Jan

STL4:05 p.m.Lambert-St Louis

2h 01m

YYZ7:06 p.m.Toronto Pearson Intl

C$ 549

Find similar

Air Canada

6 Mar

YYZ2:00 p.m.Toronto Pearson Intl

2h 29m

STL3:29 p.m.Lambert-St Louis

8 Mar

STL8:19 a.m.Lambert-St Louis

4h 42m

1 stop

YYZ2:01 p.m.Toronto Pearson Intl

C$ 620

Find similar

Fly from

Fly to

Route

Depart

Return

Price

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Tue 27/1

3:40 p.m.-11:33 p.m.

2 stops32h 53m

Lambert-St Louis

Mon 2/2

5:42 p.m.-2:08 p.m.

1 stop19h 26m

C$ 388

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Mon 12/1

7:10 a.m.-10:33 p.m.

1 stop16h 23m

Lambert-St Louis

Wed 14/1

5:11 p.m.-12:11 a.m.

1 stop30h 00m

C$ 392

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Tue 13/1

7:15 a.m.-10:34 p.m.

1 stop16h 19m

Lambert-St Louis

Fri 16/1

5:11 p.m.-2:20 p.m.

1 stop20h 09m

C$ 397

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Tue 13/1

7:15 a.m.-10:34 p.m.

1 stop16h 19m

Lambert-St Louis

Fri 16/1

8:32 p.m.-2:20 p.m.

2 stops16h 48m

C$ 410

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Thu 9/4

5:20 p.m.-9:08 p.m.

1 stop4h 48m

Lambert-St Louis

Sat 11/4

7:45 a.m.-1:59 p.m.

1 stop5h 14m

C$ 425

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Wed 21/1

5:55 p.m.-11:59 p.m.

1 stop7h 04m

Lambert-St Louis

Sat 24/1

8:30 a.m.-2:27 p.m.

1 stop4h 57m

C$ 428

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Tue 3/2

11:30 a.m.-9:15 p.m.

1 stop10h 45m

Lambert-St Louis

Wed 4/2

6:00 a.m.-4:03 p.m.

1 stop9h 03m

C$ 439

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 8/2

3:50 p.m.-10:20 a.m.

1 stop19h 30m

Lambert-St Louis

Sun 15/2

6:33 p.m.-3:05 p.m.

1 stop19h 32m

C$ 577

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Mon 19/1

5:40 a.m.-4:37 p.m.

2 stops11h 57m

Lambert-St Louis

Sat 24/1

10:19 a.m.-12:42 a.m.

2 stops13h 23m

C$ 781

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Mon 19/1

5:40 a.m.-4:37 p.m.

2 stops11h 57m

Lambert-St Louis

Sat 24/1

10:19 a.m.-12:42 a.m.

2 stops13h 23m

C$ 790

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Region of Ontario to St. Louis

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Other information

What is the cheapest month to fly to St. Louis?

The month of June is, on average, the cheapest month to fly to St. Louis from Region of Ontario, with most prices found around C$ 512. If you don’t want to visit St. Louis in June, then you should wait until August to fly from Region of Ontario, when ticket prices are also cheap, with an average price of C$ 547.

What is the cheapest day to depart on your flight to St. Louis?

Our data shows that Thursday is the least expensive day to fly to St. Louis. Tickets to fly out on this day can be as low as C$ 559. The most expensive day to fly to St. Louis is Sunday, with ticket prices averaging around C$ 735.

What is the cheapest time of day to depart on your flight to St. Louis?

The cheapest time of day to fly to St. Louis is in the morning when flights can be purchased for as low as C$ 539. If you have a flexible travel schedule, then try to avoid flying at noon when prices are C$ 662 on average. Flights to St. Louis from Region of Ontario at noon are generally more expensive because this time of day is more convenient for travellers’ schedules.

What is the cheapest Ontario to Lambert-St Louis flight route?

Fly from Toronto Pearson Intl to Lambert-St Louis for the best Ontario - Lambert-St Louis flight prices

How far in advance should I book a flight to St. Louis?

You are more likely to see cheaper flights to St. Louis from Region of Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around C$ 651 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Region of Ontario for as low as C$ 496 on momondo.

What cabin class options are available on Ontario to Lambert-St Louis flights?

There is only 1 cabin class available to choose from on Ontario to Lambert-St Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Region of Ontario to St. Louis flights?

You could potentially save up to 42% on your flight if you consider stops on a Region of Ontario to St. Louis flight.

Cheap Region of Ontario to St. Louis flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Region of Ontario to St. Louis

Best price found	C$ 555
Fastest flight time	2h 06m
Direct flights	Every day
Airports in St. Louis	1 airport

The best one-way flight to St. Louis from Region of Ontario in the past 72 hours is C$ 555. The best round-trip flight deal from Region of Ontario to St. Louis found on momondo in the last 72 hours is C$ 476.

The fastest flight from Region of Ontario to St. Louis takes 2h 06m

Direct flights go from Region of Ontario to St. Louis every day.

There is 1 airport in St. Louis. From Region of Ontario there are direct flights to Lambert-St Louis (STL).

Search flight deals

When did momondo last update prices for flights from Ontario to Lambert-St Louis Airport?
Prices for flights from Ontario to Lambert-St Louis Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Ontario to Lambert-St Louis Airport?
The number of operators available for flights from Ontario to Lambert-St Louis Airport is 5 as of December 2025.
How old do you have to be to fly from Ontario to Lambert-St Louis Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The travel and health documents you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Region of Ontario to St. Louis?
momondo data reveals that the most frequently booked plane model on the route from Region of Ontario to St. Louis is Embraer 175, representing 57.28% of all bookings. The subsequent popular models are Canadair (Bombardier) Regional Jet 900 at 23.30%, Airbus A319 at 5.83%, and Airbus A320-100/200 at 5.83%.

Best airlines flying from Region of Ontario to St. Louis

Compare and see reviews for airlines that fly from Region of Ontario to St. Louis with momondo

Airline	Rating	Free Cancellation	Price
American Airlines	PriceFrom C$ 371	Free Cancellation	Rating 7.2 11,050 reviews	Search American Airlines flights
United Airlines	PriceFrom C$ 412	Free Cancellation	Rating 7.4 9,106 reviews	Search United Airlines flights
Air Canada	PriceFrom C$ 459	Free Cancellation	Rating 7.1 10,551 reviews	Search Air Canada flights
Delta	PriceFrom C$ 473	Free Cancellation	Rating 7.9 8,014 reviews	Search Delta flights
WestJet	PriceFrom C$ 556	Free Cancellation	Rating 7.2 3,216 reviews	Search WestJet flights

Chesterfield

Litchfield

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to St. Louis?

It is quick and easy to find Ontario to St. Louis flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to St. Louis that suits you.

Can I find flights from Ontario to St. Louis with flexible booking policies on momondo?

Flights from Ontario to St. Louis with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from Ontario to St. Louis?

Once you have performed a search for Ontario to St. Louis flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Ontario to St. Louis right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to St. Louis from Ontario. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

An easier way to manage your St. Louis trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

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Cheap flights from Ontario to St. Louis from C$ 184

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to St. Louis departing on 5/2. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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United Airlines flights from Region of Ontario to St. Louis

Our best United Airlines deals on Region of Ontario to St. Louis flight tickets

Air Canada flights from Region of Ontario to St. Louis

Our best Air Canada deals on Region of Ontario to St. Louis flight tickets

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Use the filters below to find and compare flights from Ontario to St. Louis that are best for you.

See travel insights to St. Louis from

How to get the cheapest flight ticket from Region of Ontario to St. Louis

What is the cheapest month to fly to St. Louis?

What is the cheapest day to depart on your flight to St. Louis?

Our data shows that Thursday is the least expensive day to fly to St. Louis. Tickets to fly out on this day can be as low as C$ 559. The most expensive day to fly to St. Louis is Sunday, with ticket prices averaging around C$ 735.

What is the cheapest time of day to depart on your flight to St. Louis?

What is the cheapest Ontario to Lambert-St Louis flight route?

Fly from Toronto Pearson Intl to Lambert-St Louis for the best Ontario - Lambert-St Louis flight prices

How far in advance should I book a flight to St. Louis?

What cabin class options are available on Ontario to Lambert-St Louis flights?

There is only 1 cabin class available to choose from on Ontario to Lambert-St Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Region of Ontario to St. Louis flights?

You could potentially save up to 42% on your flight if you consider stops on a Region of Ontario to St. Louis flight.

What is the cheapest airline that flies from Ontario to Lambert-St Louis?

Air Canada, United Airlines, and Delta are the most popular carriers operating from Ontario to Lambert-St Louis

Which airlines fly to St. Louis?

How many flights depart from Region of Ontario to St. Louis on average per day?

2 flights are operational daily from Region of Ontario to St. Louis as of December 2025. The most popular departure time for this route is 2:00p.m., with 100% of flights per day taking off in the afternoon.

How many flights depart from Region of Ontario to St. Louis on average per week?

The number of flights available between Region of Ontario and St. Louis is 14 per week as of December 2025. The most frequent departure day is Mon, with 14% of weekly flights leaving on this day.

How long does it take to fly to St. Louis?

Cheap Region of Ontario to St. Louis flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Region of Ontario to St. Louis

Best price found

Fastest flight time

Direct flights

Airports in St. Louis

When did momondo last update prices for flights from Ontario to Lambert-St Louis Airport?

How many operators does momondo search for flights from Ontario to Lambert-St Louis Airport?

How old do you have to be to fly from Ontario to Lambert-St Louis Airport?

What documentation or ID do you need to fly to Lambert-St Louis Airport?

What is the most popular plane model from Region of Ontario to St. Louis?

Best airlines flying from Region of Ontario to St. Louis

Compare and see reviews for airlines that fly from Region of Ontario to St. Louis with momondo

Travelling to a place near St. Louis?

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to St. Louis?

Can I find flights from Ontario to St. Louis with flexible booking policies on momondo?

How can momondo help me find flights from Ontario to St. Louis?

I’m not ready to book a flight from Ontario to St. Louis right now. Can momondo alert me if prices change?

An easier way to manage your St. Louis trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United States

Airports servicing Missouri