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

Flight times from Region of Ontario to St. Louis vary, but if you’re flying out of Toronto and flying into St. Louis (one of the most popular routes), then the duration is 2h 14m on average. Another popular route from Region of Ontario to St. Louis is flying from Ottawa to St. Louis, which will take roughly 6h. Keep in mind that layovers or delays could extend your travel time.

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

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

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

As of November 2025, 1 flights take off from Region of Ontario and land in St. Louis each day. The most common flight departure time for this route is 2:00PM, with 100% of daily flights 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 12 per week as of November 2025. The most frequent departure day is Tue, with 17% of weekly flights leaving on this day.

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 refresh daily.

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

As of November 2025, there are 3 operators available to choose from 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?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for 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 required for your trip to Lambert-St Louis Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Lambert-St Louis Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

$150 Cheap Flights from Ontario to St. Louis in 2025/26

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9:30 am - 10:37 pmYOW-STL

14h 07m1 stop

5:11 pm - 5:13 pmSTL-YOW

23h 02m1 stop

$257Multiple Airlines

Find Deal

Fri, Jan 16 - Sun, Jan 25

1:10 pm - 11:38 pmYYZ-STL

11h 28m1 stop

5:15 am - 4:03 pmSTL-YYZ

9h 48m1 stop

$270American Airlines

Find Deal

Thu, Dec 4 - Mon, Dec 15

7:15 am - 10:33 pmYYZ-STL

16h 18m1 stop

3:30 pm - 2:20 pmSTL-YYZ

21h 50m1 stop

$285Multiple Airlines

Find Deal

Thu, Dec 11 - Sun, Dec 14

5:55 pm - 11:59 pmYOW-STL

7h 04m1 stop

8:05 am - 5:12 pmSTL-YOW

8h 07m1 stop

$300United Airlines

Find Deal

Fri, Jan 23 - Sun, Jan 25

6:00 am - 1:49 pmYYZ-STL

8h 49m1 stop

6:33 pm - 10:57 amSTL-YYZ

15h 24m1 stop

$305American Airlines

Find Deal

Tue, Feb 24 - Sat, Feb 28

2:50 pm - 10:58 pmYOW-STL

9h 08m2 stops

6:30 am - 5:42 pmSTL-YOW

10h 12m2 stops

$352Air Canada

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Fri, Jan 23 - Sun, Jan 25

2:48 pm - 7:48 pmYOW-STL

6h 00m1 stop

9:30 am - 9:14 pmSTL-YOW

10h 44m2 stops

$357United Airlines

Find Deal

Tue, Apr 7 - Wed, Apr 8

5:45 am - 2:18 pmYOW-STL

9h 33m2 stops

4:05 pm - 11:04 pmSTL-YOW

5h 59m1 stop

$358Air Canada

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Tue, Apr 7 - Wed, Apr 8

6:30 am - 12:04 pmYYZ-STL

6h 34m1 stop

6:40 am - 11:24 amSTL-YYZ

3h 44m1 stop

$389Delta

Find Deal

Sat, Nov 22 - Sat, Nov 29

12:08 pm - 5:09 pmYYZ-STL

6h 01m1 stop

6:40 am - 11:24 amSTL-YYZ

3h 44m1 stop

$390Delta

Find Deal

Tue, Nov 25 - Fri, Nov 28

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

Jan 23

YOW5:55 pmOttawa

7h 04m

1 stop

STL11:59 pmLambert-St Louis

Jan 25

STL8:05 amLambert-St Louis

8h 07m

1 stop

YOW5:12 pmOttawa

$300

Find similar

United Airlines

Apr 7

YOW2:48 pmOttawa

6h 00m

1 stop

STL7:48 pmLambert-St Louis

Apr 8

STL9:30 amLambert-St Louis

10h 44m

2 stops

YOW9:14 pmOttawa

$357

Find similar

United Airlines

Jan 16

YOW6:00 amOttawa

7h 29m

2 stops

STL12:29 pmLambert-St Louis

Jan 25

STL6:30 amLambert-St Louis

7h 00m

2 stops

YOW2:30 pmOttawa

$359

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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

Jan 23

YOW2:50 pmOttawa

9h 08m

2 stops

STL10:58 pmLambert-St Louis

Jan 25

STL6:30 amLambert-St Louis

10h 12m

2 stops

YOW5:42 pmOttawa

$352

Find similar

Air Canada

Apr 7

YOW5:45 amOttawa

9h 33m

2 stops

STL2:18 pmLambert-St Louis

Apr 8

STL4:05 pmLambert-St Louis

5h 59m

1 stop

YOW11:04 pmOttawa

$358

Find similar

Air Canada

Nov 22

YYZ2:00 pmToronto Pearson Intl

2h 29m

STL3:29 pmLambert-St Louis

Nov 24

STL4:05 pmLambert-St Louis

2h 01m

YYZ7:06 pmToronto Pearson Intl

$369

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Fly from

Fly to

Route

Depart

Return

Price

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 1/16

9:30 am-10:37 pm

1 stop14h 07m

Lambert-St Louis

Sun 1/25

5:11 pm-5:13 pm

1 stop23h 02m

$257

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Thu 12/4

1:10 pm-11:38 pm

1 stop11h 28m

Lambert-St Louis

Mon 12/15

5:15 am-4:03 pm

1 stop9h 48m

$270

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Thu 12/11

7:15 am-10:33 pm

1 stop16h 18m

Lambert-St Louis

Sun 12/14

3:30 pm-2:20 pm

1 stop21h 50m

$285

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 1/23

5:55 pm-11:59 pm

1 stop7h 04m

Lambert-St Louis

Sun 1/25

8:05 am-5:12 pm

1 stop8h 07m

$300

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Tue 2/24

6:00 am-1:49 pm

1 stop8h 49m

Lambert-St Louis

Sat 2/28

6:33 pm-10:57 am

1 stop15h 24m

$305

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 1/23

2:50 pm-10:58 pm

2 stops9h 08m

Lambert-St Louis

Sun 1/25

6:30 am-5:42 pm

2 stops10h 12m

$352

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Tue 4/7

2:48 pm-7:48 pm

1 stop6h 00m

Lambert-St Louis

Wed 4/8

9:30 am-9:14 pm

2 stops10h 44m

$357

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Tue 4/7

5:45 am-2:18 pm

2 stops9h 33m

Lambert-St Louis

Wed 4/8

4:05 pm-11:04 pm

1 stop5h 59m

$358

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Sat 11/22

6:30 am-12:04 pm

1 stop6h 34m

Lambert-St Louis

Sat 11/29

6:40 am-11:24 am

1 stop3h 44m

$389

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Tue 11/25

12:08 pm-5:09 pm

1 stop6h 01m

Lambert-St Louis

Fri 11/28

6:40 am-11:24 am

1 stop3h 44m

$390

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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

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Other information

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

In general, June is the cheapest month to fly from Region of Ontario to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $372. The month of August is another great option to travel to St. Louis, with average flight prices from Region of Ontario averaging around $397.

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

The cheapest day to depart on your flight to St. Louis is on a Tuesday when prices can be found for as low as $391. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $541. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

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

Flying to St. Louis from Region of Ontario in the morning is the least expensive time of day to depart. momondo users have found prices as low as $326 when looking at flights departing in the morning. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $483 per ticket.

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 $490 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 $360 on momondo.

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

There are 3 cabin classes 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 25% 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	$323
Fastest flight time	2h 14m
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 $323. The best round-trip flight deal from Region of Ontario to St. Louis found on momondo in the last 72 hours is $476.

The fastest flight from Region of Ontario to St. Louis takes 2h 14m

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

There is 1 airport near St. Louis: 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 refresh daily.
How many operators does momondo search for flights from Ontario to Lambert-St Louis Airport?
As of November 2025, there are 3 operators available to choose from 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?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for 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 required for your trip to Lambert-St Louis Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Lambert-St Louis Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Region of Ontario to St. Louis?
Based on momondo bookings for flights between Region of Ontario and St. Louis, the leading plane model is Canadair (Bombardier) Regional Jet 900, making up 58.90% of the total bookings. Other popular models include Embraer 175 with 27.40%, Airbus A319 with 4.11%, and Airbus A320-100/200 with 4.11%.

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
Air Canada	PriceFrom $324	Free Cancellation	Rating 7.1 10,416 reviews		Search Air Canada flights
United Airlines	PriceFrom $422	Free Cancellation	Rating 7.4 9,007 reviews		Search United Airlines flights

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Why use momondo?

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

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Ontario to St. Louis. Millions of users trust and use momondo every year so you are in good hands.

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 all potential Ontario to St. Louis flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

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

Price alerts on flights to St. Louis from Ontario are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.

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Cheap flights from Ontario to St. Louis from $150

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 1/29. 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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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

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

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

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 are 3 cabin classes 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 25% 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?

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

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

As of November 2025, 1 flights take off from Region of Ontario and land in St. Louis each day. The most common flight departure time for this route is 2:00PM, with 100% of daily flights 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 12 per week as of November 2025. The most frequent departure day is Tue, with 17% 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

Traveling 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.

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