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

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

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

As of October 2025, 2 flights take off from St. Louis and land in Region of Ontario each day. The most common flight departure time for this route is 9:00a.m., with 50% of daily flights taking off at noon.

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

As of October 2025, there are 16 flights per week flying from St. Louis to Region of Ontario. The most common day of the week flights depart is Wed, with 25% of flights taking off on this day.

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 are refreshed on a daily basis.

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

There is 1 operator available for flights from Lambert-St Louis Airport to Ontario as of October 2025.

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 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 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.

C$ 161 Cheap Flights from St. Louis to Ontario in 2025/26

1 adult

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Find the cheapest flights from St. Louis to Ontario

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6:04 a.m. - 5:20 p.m.STL-YYZ

10h 16m1 stop

11:25 a.m. - 9:44 p.m.YYZ-STL

11h 19m1 stop

C$ 377American Airlines

Find Deal

Sat, 14 Feb - Sat, 21 Feb

8:38 a.m. - 5:44 p.m.STL-YYZ

8h 06m1 stop

6:00 a.m. - 7:06 p.m.YYZ-STL

14h 06m1 stop

C$ 379American Airlines

Find Deal

Fri, 5 Dec - Sat, 6 Dec

10:48 a.m. - 9:19 p.m.STL-YYZ

33h 31m2 stops

7:15 a.m. - 10:33 p.m.YYZ-STL

16h 18m1 stop

C$ 447Multiple Airlines

Find Deal

Tue, 23 Dec - Tue, 6 Jan

2:57 p.m. - 2:40 p.m.STL-YYZ

22h 43m1 stop

8:30 p.m. - 9:52 a.m.YYZ-STL

14h 22m2 stops

C$ 465Multiple Airlines

Find Deal

Thu, 11 Dec - Sun, 14 Dec

4:05 p.m. - 7:06 p.m.STL-YYZ

2h 01mdirect

2:00 p.m. - 3:29 p.m.YYZ-STL

2h 29mdirect

C$ 560Air Canada

Find Deal

Thu, 11 Dec - Sun, 14 Dec

4:05 p.m. - 7:06 p.m.STL-YYZ

2h 01mdirect

2:00 p.m. - 3:29 p.m.YYZ-STL

2h 29mdirect

C$ 563Air Canada

Find Deal

Fri, 5 Dec - Fri, 12 Dec

7:41 a.m. - 11:59 p.m.STL-YYZ

15h 18m1 stop

3:30 p.m. - 10:59 p.m.YYZ-STL

8h 29m1 stop

C$ 582United Airlines

Find Deal

Tue, 3 Mar - Wed, 4 Mar

8:05 a.m. - 9:16 p.m.STL-YUL

12h 11m2 stops

10:50 a.m. - 10:58 p.m.YUL-STL

13h 08m2 stops

C$ 644United Airlines

Find Deal

Sat, 10 Jan - Wed, 28 Jan

6:00 a.m. - 6:40 p.m.STL-YUL

11h 40m1 stop

7:45 p.m. - 8:20 a.m.YUL-STL

13h 35m1 stop

C$ 728Delta

Find Deal

Mon, 24 Nov - Tue, 2 Dec

6:40 a.m. - 6:40 p.m.STL-YUL

11h 00m2 stops

7:45 p.m. - 8:20 a.m.YUL-STL

13h 35m1 stop

C$ 788Delta

Find Deal

Mon, 24 Nov - Tue, 2 Dec

American Airlines flights from St. Louis to Region of Ontario

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

American Airlines

14 Feb

STL6:04 a.m.Lambert-St Louis

10h 16m

1 stop

YYZ5:20 p.m.Toronto Pearson Intl

21 Feb

YYZ11:25 a.m.Toronto Pearson Intl

11h 19m

1 stop

STL9:44 p.m.Lambert-St Louis

C$ 377

Find similar

American Airlines

5 Dec

STL8:38 a.m.Lambert-St Louis

8h 06m

1 stop

YYZ5:44 p.m.Toronto Pearson Intl

6 Dec

YYZ6:00 a.m.Toronto Pearson Intl

14h 06m

1 stop

STL7:06 p.m.Lambert-St Louis

C$ 379

Find similar

American Airlines

12 Dec

STL8:38 a.m.Lambert-St Louis

8h 06m

1 stop

YYZ5:44 p.m.Toronto Pearson Intl

14 Dec

YYZ6:00 a.m.Toronto Pearson Intl

9h 50m

1 stop

STL2:50 p.m.Lambert-St Louis

C$ 381

Find similar

WestJet flights from St. Louis to Region of Ontario

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

WestJet

1 Nov

STL3:59 p.m.Lambert-St Louis

27h 37m

2 stops

YYZ8:36 p.m.Toronto Pearson Intl

4 Nov

YYZ6:45 p.m.Toronto Pearson Intl

21h 44m

1 stop

STL3:29 p.m.Lambert-St Louis

C$ 1,252

Find similar

WestJet

24 Oct

STL6:00 a.m.Lambert-St Louis

23h 52m

2 stops

YYZ6:52 a.m.Toronto Pearson Intl

25 Oct

YYZ6:30 p.m.Toronto Pearson Intl

22h 40m

2 stops

STL4:10 p.m.Lambert-St Louis

C$ 1,950

Find similar

WestJet

25 Oct

STL6:40 a.m.Lambert-St Louis

3h 40m

1 stop

YYZ11:20 a.m.Toronto Pearson Intl

27 Oct

YYZ9:45 a.m.Toronto Pearson Intl

4h 37m

1 stop

STL1:22 p.m.Lambert-St Louis

C$ 2,365

Find similar

Fly from

Fly to

Route

Depart

Return

Price

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Sat 14/2

6:04 a.m.-5:20 p.m.

1 stop10h 16m

Toronto Pearson Intl

Sat 21/2

11:25 a.m.-9:44 p.m.

1 stop11h 19m

C$ 377

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Fri 5/12

8:38 a.m.-5:44 p.m.

1 stop8h 06m

Toronto Pearson Intl

Sat 6/12

6:00 a.m.-7:06 p.m.

1 stop14h 06m

C$ 379

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 23/12

10:48 a.m.-9:19 p.m.

2 stops33h 31m

Toronto Pearson Intl

Tue 6/1

7:15 a.m.-10:33 p.m.

1 stop16h 18m

C$ 447

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Thu 11/12

2:57 p.m.-2:40 p.m.

1 stop22h 43m

Toronto Pearson Intl

Sun 14/12

8:30 p.m.-9:52 a.m.

2 stops14h 22m

C$ 465

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Thu 11/12

4:05 p.m.-7:06 p.m.

Nonstop2h 01m

Toronto Pearson Intl

Sun 14/12

2:00 p.m.-3:29 p.m.

Nonstop2h 29m

C$ 560

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Fri 5/12

4:05 p.m.-7:06 p.m.

Nonstop2h 01m

Toronto Pearson Intl

Fri 12/12

2:00 p.m.-3:29 p.m.

Nonstop2h 29m

C$ 563

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 3/3

7:41 a.m.-11:59 p.m.

1 stop15h 18m

Toronto Pearson Intl

Wed 4/3

3:30 p.m.-10:59 p.m.

1 stop8h 29m

C$ 582

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 10/1

8:05 a.m.-9:16 p.m.

2 stops12h 11m

Montreal Pierre Elliott Trudeau Intl

Wed 28/1

10:50 a.m.-10:58 p.m.

2 stops13h 08m

C$ 644

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Mon 24/11

6:00 a.m.-6:40 p.m.

1 stop11h 40m

Montreal Pierre Elliott Trudeau Intl

Tue 2/12

7:45 p.m.-8:20 a.m.

1 stop13h 35m

C$ 728

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Mon 24/11

6:40 a.m.-6:40 p.m.

2 stops11h 00m

Montreal Pierre Elliott Trudeau Intl

Tue 2/12

7:45 p.m.-8:20 a.m.

1 stop13h 35m

C$ 788

Flights are sorted by cheapest round-trip flights first.

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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?

In general, January is the cheapest month to fly from St. Louis to Region of Ontario. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around C$ 400. If you are unable to visit Region of Ontario during the month of January, then departing from St. Louis during the month April is also very affordable. Most momondo users find prices during this month for around C$ 440.

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

The cheapest day to depart from St. Louis to Region of Ontario is on a Friday. Travellers who choose to depart for Region of Ontario on a Friday will often find tickets for as low as C$ 519. The most expensive day to fly to Region of Ontario is Sunday, with ticket prices averaging around C$ 939.

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

Our most recent data shows that the best time of day to fly to Region of Ontario is at noon. Flights from St. Louis to Region of Ontario during this time can be as low as C$ 600. If you have a flexible travel schedule, then try to avoid flying in the afternoon when prices are C$ 779 on average. Flights to Region of Ontario from St. Louis in the afternoon are generally more expensive because this time of day is more convenient for travellers’ schedules.

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

How far in advance should I book a flight to Region of Ontario?

You are more likely to see cheaper flights to Region of Ontario from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Region of Ontario for around C$ 683 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Region of Ontario from St. Louis for as low as C$ 309 on momondo.

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

There is only 1 cabin class available to choose from on Lambert-St Louis to 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 24% 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	C$ 261
Fastest flight time	2h 01m
Direct flights	Every day
Airports in Region of Ontario	1 airport

The best flight deal from St. Louis to Region of Ontario found on momondo in the last 72 hours is C$ 261

The fastest flight from St. Louis to Region of Ontario takes 2h 01m

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

There is 1 airport near Region of Ontario: Toronto Pearson Intl (YYZ)

Search flight deals

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 are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Ontario?
There is 1 operator available for flights from Lambert-St Louis Airport to Ontario as of October 2025.
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 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 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 57.46% of all bookings. The subsequent popular models are Embraer 175 at 15.67%, Airbus A330-300 at 4.48%, and Boeing 737 MAX 8 at 2.99%.

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 C$ 305	Free Cancellation	Rating 7.1 10,350 reviews		Search Air Canada flights

Why use momondo?

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

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from St. Louis to Ontario for you.

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

Yes. momondo allows you to filter the results for St. Louis to Ontario flights to just show those with flexible booking policies.

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

momondo helps you find the best flight between St. Louis and Ontario by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

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 not ready to book a flight from St. Louis to Ontario now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Ontario and let you know when they change.

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.

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Find better results for your trip to Ontario

Popular Cities in Ontario

Flights to Torontofrom C$ 108

Flights to Vancouverfrom C$ 66

Flights to Montrealfrom C$ 241

Flights to Calgaryfrom C$ 83

Flights to Ottawafrom C$ 216

Flights to Winnipegfrom C$ 139

Flights to Halifaxfrom C$ 106

Flights to Kelownafrom C$ 102

Flights to Saskatoonfrom C$ 133

Flights to Reginafrom C$ 154

Flights to St. John'sfrom C$ 216

Flights to Québec Cityfrom C$ 290

Cheap flights from St. Louis to Ontario from C$ 161

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 7/12. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Big names, great deals

Big names, great deals

Filter for what you want

Filter for what you want

Trusted and free

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Find the cheapest flights from St. Louis to Ontario

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Cheap one-way flights

Cheap last-minute flights

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American Airlines flights from St. Louis to Region of Ontario

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

WestJet flights from St. Louis to Region of Ontario

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

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

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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

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?

The cheapest day to depart from St. Louis to Region of Ontario is on a Friday. Travellers who choose to depart for Region of Ontario on a Friday will often find tickets for as low as C$ 519. The most expensive day to fly to Region of Ontario is Sunday, with ticket prices averaging around C$ 939.

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?

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

How far in advance should I book a flight to Region of Ontario?

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

There is only 1 cabin class available to choose from on Lambert-St Louis to 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 24% on your flight if you consider stops on a St. Louis to Region of Ontario flight.

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

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

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

As of October 2025, 2 flights take off from St. Louis and land in Region of Ontario each day. The most common flight departure time for this route is 9:00a.m., with 50% of daily flights taking off at noon.

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

As of October 2025, there are 16 flights per week flying from St. Louis to Region of Ontario. The most common day of the week flights depart is Wed, with 25% of flights taking off on this day.

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

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

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

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

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

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

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

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

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

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

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