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

6 flights are operational daily from St. Louis to Region of Ontario as of June 2026. The most popular departure time for this route is 8:00AM, with 50% of flights per day taking off at noon.

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

As of June 2026, there are 42 flights per week flying from St. Louis to Region of Ontario. The most common day of the week flights depart is Mon, with 14% of flights taking off on this day.

What airlines fly to Region of Ontario?

Air Canada, United Airlines and American Airlines are the top three most popular airlines that fly to Region of Ontario from St. Louis according to our data. Air Canada is the first choice among our users, with 67% of people opting to fly with this airline when traveling to Region of Ontario. Keep in mind that there are 3 different airlines that fly to Region of Ontario on a routine basis, so you have a few additional options to choose from.

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

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

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

Prices for flights from Lambert-St Louis Airport to Ontario were last updated today.

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

The number of operators available for flights from Lambert-St Louis Airport to Ontario is 3 as of June 2026.

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

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Ontario.

What documentation or ID do you need to fly to Ontario?

The required travel and health documents for your Ontario trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ontario. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

$201 Cheap Flights from St. Louis to Ontario in 2026

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from St. Louis to Ontario

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

Enter your travel dates to find the best prices.

12:10 pm - 7:45 pm

STL

YOW

6h 35m

1 stop

2:35 pm - 6:42 pm

YOW

STL

5h 07m

1 stop

$390Air Canada

Tue, Jul 7 - Tue, Jul 14

7:03 pm - 6:39 am

STL

YYZ

10h 36m

1 stop

4:45 pm - 6:36 pm

YYZ

STL

26h 51m

2 stops

$429Multiple Airlines

Wed, Jul 8 - Sun, Jul 12

6:34 pm - 12:00 pm

STL

YYZ

16h 26m

2 stops

8:35 pm - 6:05 pm

YYZ

STL

22h 30m

1 stop

$436Multiple Airlines

Tue, Jul 14 - Mon, Jul 20

4:57 pm - 9:25 pm

STL

YYZ

27h 28m

2 stops

8:35 pm - 6:15 pm

YYZ

STL

22h 40m

1 stop

$448Multiple Airlines

Mon, Jul 13 - Wed, Jul 22

6:34 pm - 12:00 pm

STL

YYZ

16h 26m

2 stops

7:00 am - 6:05 pm

YYZ

STL

12h 05m

1 stop

$451Multiple Airlines

Tue, Jul 14 - Tue, Jul 21

6:34 pm - 12:00 pm

STL

YYZ

16h 26m

2 stops

9:50 am - 11:59 pm

YYZ

STL

15h 09m

1 stop

$455Multiple Airlines

Tue, Jul 21 - Fri, Jul 24

4:57 pm - 9:25 pm

STL

YYZ

27h 28m

2 stops

7:00 am - 6:05 pm

YYZ

STL

12h 05m

1 stop

$463Multiple Airlines

Mon, Jul 13 - Tue, Jul 21

12:59 pm - 10:35 pm

STL

YOW

8h 36m

2 stops

2:00 pm - 8:00 pm

YOW

STL

7h 00m

1 stop

$474United Airlines

Sat, Sep 19 - Wed, Sep 23

9:23 am - 5:16 pm

STL

YOW

6h 53m

1 stop

6:00 am - 3:38 pm

YOW

STL

10h 38m

3 stops

$477United Airlines

Sat, Sep 19 - Wed, Sep 23

6:55 am - 4:50 pm

STL

YUL

8h 55m

1 stop

5:34 pm - 8:23 am

YUL

STL

15h 49m

1 stop

$517American Airlines

Tue, Aug 4 - Tue, Aug 11

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WestJet flights from St. Louis to Region of Ontario

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

WestJet

Jul 21

STL3:58 pmLambert-St Louis

6h 54m

1 stop

YUL11:52 pmMontreal Pierre Elliott Trudeau Intl

Jul 28

YUL7:00 amMontreal Pierre Elliott Trudeau Intl

6h 17m

1 stop

STL12:17 pmLambert-St Louis

$560

WestJet

Jul 4

STL6:10 pmLambert-St Louis

4h 18m

1 stop

YUL11:28 pmMontreal Pierre Elliott Trudeau Intl

Jul 6

YUL9:30 amMontreal Pierre Elliott Trudeau Intl

7h 20m

1 stop

STL3:50 pmLambert-St Louis

$583

WestJet

Jun 21

STL10:51 amLambert-St Louis

5h 28m

1 stop

YYZ5:19 pmToronto Pearson Intl

Jun 24

YYZ6:30 amToronto Pearson Intl

4h 58m

1 stop

STL10:28 amLambert-St Louis

$601

Air Canada flights from St. Louis to Region of Ontario

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

Air Canada

Jul 7

STL12:10 pmLambert-St Louis

6h 35m

1 stop

YOW7:45 pmOttawa

Jul 14

YOW2:35 pmOttawa

5h 07m

1 stop

STL6:42 pmLambert-St Louis

$390

Air Canada

Sep 19

STL8:55 amLambert-St Louis

5h 15m

1 stop

YOW3:10 pmOttawa

Sep 23

YOW3:10 pmOttawa

4h 31m

1 stop

STL6:41 pmLambert-St Louis

$463

Air Canada

Jun 25

STL2:15 pmLambert-St Louis

1h 51m

YYZ5:06 pmToronto Pearson Intl

Jun 28

YYZ11:15 amToronto Pearson Intl

2h 06m

STL12:21 pmLambert-St Louis

$493

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Quickest round-trip

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Tue 7/7

12:10 pm-7:45 pm

1 stop6h 35m

Ottawa

Tue 7/14

2:35 pm-6:42 pm

1 stop5h 07m

$390

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Wed 7/8

7:03 pm-6:39 am

1 stop10h 36m

Toronto Pearson Intl

Sun 7/12

4:45 pm-6:36 pm

2 stops26h 51m

$429

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 7/14

6:34 pm-12:00 pm

2 stops16h 26m

Toronto Pearson Intl

Mon 7/20

8:35 pm-6:05 pm

1 stop22h 30m

$436

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Mon 7/13

4:57 pm-9:25 pm

2 stops27h 28m

Toronto Pearson Intl

Wed 7/22

8:35 pm-6:15 pm

1 stop22h 40m

$448

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 7/14

6:34 pm-12:00 pm

2 stops16h 26m

Toronto Pearson Intl

Tue 7/21

7:00 am-6:05 pm

1 stop12h 05m

$451

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 7/21

6:34 pm-12:00 pm

2 stops16h 26m

Toronto Pearson Intl

Fri 7/24

9:50 am-11:59 pm

1 stop15h 09m

$455

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Mon 7/13

4:57 pm-9:25 pm

2 stops27h 28m

Toronto Pearson Intl

Tue 7/21

7:00 am-6:05 pm

1 stop12h 05m

$463

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 9/19

12:59 pm-10:35 pm

2 stops8h 36m

Ottawa

Wed 9/23

2:00 pm-8:00 pm

1 stop7h 00m

$474

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 9/19

9:23 am-5:16 pm

1 stop6h 53m

Ottawa

Wed 9/23

6:00 am-3:38 pm

3 stops10h 38m

$477

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Tue 8/4

6:55 am-4:50 pm

1 stop8h 55m

Montreal Pierre Elliott Trudeau Intl

Tue 8/11

5:34 pm-8:23 am

1 stop15h 49m

$517

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 St. Louis to Region of Ontario

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 Region of Ontario?

The month of July is, on average, the cheapest month to fly to Region of Ontario from St. Louis, with most prices found around $139. If you aren’t able to travel during the month of July, then book flights to Region of Ontario from St. Louis during June instead. Flights to Region of Ontario in June, while not as cheap as those in July, still average around $139.

What is the cheapest day to depart on your flight to Region of Ontario?

According to our data, Friday is the cheapest day to fly to Region of Ontario from St. Louis. The lowest ticket price found for a Friday departure recently was $804. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Flights from St. Louis to Region of Ontario on a Thursday will generally be more expensive and average around $935. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Region of Ontario?

According to our data, the cheapest time of day to fly to Region of Ontario is in the afternoon. momondo users have found flights departing from St. Louis to Region of Ontario in the afternoon for as low as $787. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights at noon are often more expensive with an average ticket price of $1,077.

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

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

What cabin class options are available on St. Louis to Region of Ontario flights?

There are 4 cabin classes available to choose from on St. Louis to Region of Ontario 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 St. Louis to Region of Ontario flights?

You could potentially save up to 32% on your flight if you consider stops on a St. Louis to Region of Ontario flight.

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

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

Best Price Found	$404
Fastest flight time	1h 51m
Direct flights	Every day
Airports in Region of Ontario	125 airports

The best one-way flight to Region of Ontario from St. Louis in the past 72 hours is $404. The best round-trip flight deal from St. Louis to Region of Ontario found on momondo in the last 72 hours is $360.

The fastest flight from St. Louis to Region of Ontario takes 1h 51m

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

There are 125 airports in Region of Ontario. From St. Louis there are direct flights to Montreal Pierre Elliott Trudeau Intl (YUL), Toronto Pearson Intl (YYZ).

Search flight deals

Frequently asked questions about flying from St. Louis to Ontario

When did momondo last update prices for flights from Lambert-St Louis Airport to Ontario?
Prices for flights from Lambert-St Louis Airport to Ontario were last updated today.
How many operators does momondo search for flights from Lambert-St Louis Airport to Ontario?
The number of operators available for flights from Lambert-St Louis Airport to Ontario is 3 as of June 2026.
How old do you have to be to fly from Lambert-St Louis Airport to Ontario?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Ontario.
What documentation or ID do you need to fly to Ontario?
The required travel and health documents for your Ontario trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ontario. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from St. Louis to Region of Ontario?
momondo data reveals that the most frequently booked plane model on the route from St. Louis to Region of Ontario is Canadair (Bombardier) Regional Jet 900, representing 46.40% of all bookings. The subsequent popular models are Airbus A220-300 at 30.55%, Embraer 175 at 6.63%, and Boeing 787-8 Dreamliner at 6.34%.

Best airlines flying from St. Louis to Region of Ontario

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

Airline	Rating	Free Cancellation	Price
Air Canada	PriceFrom $139	Free Cancellation	Rating 7.1 11,149 reviews	Search Air Canada flights
United Airlines	PriceFrom $203	Free Cancellation	Rating 7.4 9,797 reviews	Search United Airlines flights
American Airlines	PriceFrom $270	Free Cancellation	Rating 7.1 11,643 reviews	Search American Airlines flights

Why use momondo?

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

It is quick and easy to find St. Louis to Ontario 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 Ontario that suits you.

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

Yes. All flights to Ontario from St. Louis on momondo can be compared and filtered by various policies on offer, including flexible booking.

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

Once you have performed a search for St. Louis to Ontario 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 St. Louis to Ontario right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Ontario, momondo offers a useful price alert feature which will track prices for flights to Ontario from St. Louis and alert you when they change.

An easier way to manage your Region of Ontario trip

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Popular cities in Ontario

Flights to Torontofrom $156

Flights to Vancouverfrom $143

Flights to Montrealfrom $221

Flights to Calgaryfrom $219

Flights to Ottawafrom $256

Flights to Halifaxfrom $293

Flights to Winnipegfrom $364

Flights to Québec Cityfrom $335

Flights to Saskatoonfrom $347

Flights to Kelownafrom $265

Flights to St. John'sfrom $466

Flights to Reginafrom $414

Cheap flights from St. Louis to Ontario from $201

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Ontario departing on 8/26. 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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WestJet flights from St. Louis to Region of Ontario

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

Air Canada flights from St. Louis to Region of Ontario

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

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

What is the cheapest month to fly to Region of Ontario?

What is the cheapest day to depart on your flight to Region of Ontario?

What is the cheapest time of day to depart on your flight to Region of Ontario?

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

What cabin class options are available on St. Louis to Region of Ontario flights?

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

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

What airlines fly to Region of Ontario?

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

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

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

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

Best Price Found

Fastest flight time

Direct flights

Airports in Region of Ontario

Frequently asked questions about flying from St. Louis to Ontario

Best airlines flying from St. Louis to Region of Ontario

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

Why use momondo?

An easier way to manage your Region of Ontario 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 Ontario

Popular cities in Ontario

Popular flights according to clicks in the last 7 days on momondo

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According to popular flight searches on momondo this year

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