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

As of December 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 4:00p.m., with 100% of daily flights taking off in the afternoon.

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

As of December 2025, there are 14 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 is the cheapest airline that flies from Lambert-St Louis to Ontario?

Alaska Airlines and American Airlines 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 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 December 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$ 142 Cheap Flights from St. Louis to Ontario in 2025/26

1 adult

Discover deals from 900+ travel sites with momondo.

Save money when you book flights with momondo

Big names, great deals

Search 100s of travel sites to compare prices.

Filter for what you want

Free Wi-Fi? Early arrival? Instantly customize your results

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Not ready to book? to track prices.

Search flight deals

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.

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

STL

YYZ

29h 09m2 stops

7:10 a.m. - 11:33 p.m.

YYZ

STL

17h 23m1 stop

C$ 355Multiple Airlines

Tue, 13 Jan - Mon, 26 Jan

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

STL

YYZ

30h 00m1 stop

7:10 a.m. - 11:33 p.m.

YYZ

STL

17h 23m1 stop

C$ 388Multiple Airlines

Tue, 13 Jan - Mon, 26 Jan

1:07 p.m. - 6:20 a.m.

STL

YYZ

16h 13m1 stop

3:40 p.m. - 6:51 a.m.

YYZ

STL

40h 11m2 stops

C$ 402Multiple Airlines

Mon, 12 Jan - Mon, 19 Jan

1:07 p.m. - 6:20 a.m.

STL

YYZ

16h 13m1 stop

7:00 a.m. - 6:51 a.m.

YYZ

STL

48h 51m2 stops

C$ 405Multiple Airlines

Mon, 12 Jan - Mon, 19 Jan

6:35 p.m. - 10:56 a.m.

STL

YYZ

15h 21m1 stop

11:38 a.m. - 6:02 p.m.

YYZ

STL

7h 24m1 stop

C$ 484American Airlines

Sat, 14 Feb - Sat, 21 Feb

6:00 a.m. - 3:08 p.m.

STL

YUL

8h 08m1 stop

7:30 a.m. - 6:14 p.m.

YUL

STL

11h 44m2 stops

C$ 709American Airlines

Thu, 22 Jan - Thu, 29 Jan

6:44 p.m. - 3:08 p.m.

STL

YUL

19h 24m1 stop

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

YUL

STL

19h 30m1 stop

C$ 725American Airlines

Sun, 18 Jan - Wed, 28 Jan

4:05 p.m. - 9:20 p.m.

STL

YXU

4h 15m1 stop

9:50 a.m. - 3:29 p.m.

YXU

STL

6h 39m1 stop

C$ 1,254Air Canada

Sun, 18 Jan - Thu, 22 Jan

11:20 a.m. - 9:20 p.m.

STL

YXU

9h 00m2 stops

9:50 a.m. - 3:29 p.m.

YXU

STL

6h 39m1 stop

C$ 1,268Air Canada

Sun, 18 Jan - Thu, 22 Jan

11:20 a.m. - 9:20 p.m.

STL

YXU

9h 00m2 stops

5:10 a.m. - 4:03 p.m.

YXU

STL

11h 53m2 stops

C$ 1,289Air Canada

Sun, 18 Jan - Thu, 22 Jan

United Airlines flights from St. Louis to Region of Ontario

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

United Airlines

21 Dec

STL3:10 p.m.Lambert-St Louis

7h 36m

2 stops

YYZ11:46 p.m.Toronto Pearson Intl

27 Dec

YYZ5:30 p.m.Toronto Pearson Intl

6h 13m

1 stop

STL10:43 p.m.Lambert-St Louis

C$ 695

Find similar

United Airlines

25 Dec

STL3:10 p.m.Lambert-St Louis

7h 36m

2 stops

YYZ11:46 p.m.Toronto Pearson Intl

31 Dec

YYZ10:00 a.m.Toronto Pearson Intl

7h 27m

2 stops

STL4:27 p.m.Lambert-St Louis

C$ 702

Find similar

United Airlines

13 Jan

STL8:05 a.m.Lambert-St Louis

10h 40m

1 stop

YYZ7:45 p.m.Toronto Pearson Intl

25 Jan

YYZ2:00 p.m.Toronto Pearson Intl

2h 29m

STL3:29 p.m.Lambert-St Louis

C$ 747

Find similar

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

STL10:04 a.m.Lambert-St Louis

10h 25m

1 stop

YYZ9:29 p.m.Toronto Pearson Intl

21 Feb

YYZ11:38 a.m.Toronto Pearson Intl

7h 24m

1 stop

STL6:02 p.m.Lambert-St Louis

C$ 484

Find similar

American Airlines

14 Jan

STL6:44 p.m.Lambert-St Louis

15h 09m

1 stop

YYZ10:53 a.m.Toronto Pearson Intl

26 Jan

YYZ1:14 p.m.Toronto Pearson Intl

9h 01m

1 stop

STL9:15 p.m.Lambert-St Louis

C$ 564

Find similar

American Airlines

9 Feb

STL6:00 a.m.Lambert-St Louis

9h 03m

1 stop

YYZ4:03 p.m.Toronto Pearson Intl

12 Feb

YYZ10:57 a.m.Toronto Pearson Intl

5h 29m

1 stop

STL3:26 p.m.Lambert-St Louis

C$ 582

Find similar

Fly from

Fly to

Route

Depart

Return

Price

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 13/1

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

2 stops29h 09m

Toronto Pearson Intl

Mon 26/1

7:10 a.m.-11:33 p.m.

1 stop17h 23m

C$ 355

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 13/1

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

1 stop30h 00m

Toronto Pearson Intl

Mon 26/1

7:10 a.m.-11:33 p.m.

1 stop17h 23m

C$ 388

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Mon 12/1

1:07 p.m.-6:20 a.m.

1 stop16h 13m

Toronto Pearson Intl

Mon 19/1

3:40 p.m.-6:51 a.m.

2 stops40h 11m

C$ 402

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Mon 12/1

1:07 p.m.-6:20 a.m.

1 stop16h 13m

Toronto Pearson Intl

Mon 19/1

7:00 a.m.-6:51 a.m.

2 stops48h 51m

C$ 405

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Sat 14/2

6:35 p.m.-10:56 a.m.

1 stop15h 21m

Toronto Pearson Intl

Sat 21/2

11:38 a.m.-6:02 p.m.

1 stop7h 24m

C$ 484

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Thu 22/1

6:00 a.m.-3:08 p.m.

1 stop8h 08m

Montreal Pierre Elliott Trudeau Intl

Thu 29/1

7:30 a.m.-6:14 p.m.

2 stops11h 44m

C$ 709

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sun 18/1

6:44 p.m.-3:08 p.m.

1 stop19h 24m

Montreal Pierre Elliott Trudeau Intl

Wed 28/1

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

1 stop19h 30m

C$ 725

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Sun 18/1

4:05 p.m.-9:20 p.m.

1 stop4h 15m

London

Thu 22/1

9:50 a.m.-3:29 p.m.

1 stop6h 39m

C$ 1,254

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Sun 18/1

11:20 a.m.-9:20 p.m.

2 stops9h 00m

London

Thu 22/1

9:50 a.m.-3:29 p.m.

1 stop6h 39m

C$ 1,268

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Sun 18/1

11:20 a.m.-9:20 p.m.

2 stops9h 00m

London

Thu 22/1

5:10 a.m.-4:03 p.m.

2 stops11h 53m

C$ 1,289

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?

In general, April 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$ 434. If you are unable to visit Region of Ontario during the month of April, then departing from St. Louis during the month June is also very affordable. Most momondo users find prices during this month for around C$ 542.

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$ 580. The most expensive day to fly to Region of Ontario is Wednesday, with ticket prices averaging around C$ 899.

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$ 592. If you have a flexible travel schedule, then try to avoid flying in the morning when prices are C$ 767 on average. Flights to Region of Ontario from St. Louis in the morning 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$ 706 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$ 305 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 8% 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

Fastest flight time	1h 55m
Direct flights	Every day
Airports in Region of Ontario	2 airports

The fastest flight from St. Louis to Region of Ontario takes 1h 55m

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

There are 2 airports near Region of Ontario: Montreal Pierre Elliott Trudeau Intl (YUL), 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 December 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 Embraer 175, representing 38.38% of all bookings. The subsequent popular models are Canadair (Bombardier) Regional Jet 900 at 26.26%, Airbus A330-300 at 6.06%, and Boeing 737 MAX 8 at 4.04%.

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$ 301	Free Cancellation	Rating 7.1 10,512 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.

Start using Trips

Find my bookings

Get notified when prices go down

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

1 adult

Wed 7/1

Wed 14/1

Email me momondo's favourite deals

By creating a price alert you accept our terms of use and privacy policy.

Find better results for your trip to Ontario

Popular Cities in Ontario

Flights to Torontofrom C$ 104

Flights to Vancouverfrom C$ 72

Flights to Montrealfrom C$ 48

Flights to Calgaryfrom C$ 80

Flights to Ottawafrom C$ 99

Flights to Winnipegfrom C$ 105

Flights to Halifaxfrom C$ 57

Flights to Kelownafrom C$ 61

Flights to Saskatoonfrom C$ 193

Flights to Reginafrom C$ 191

Flights to St. John'sfrom C$ 343

Flights to Québec Cityfrom C$ 309

Cheap flights from St. Louis to Ontario from C$ 142

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 21/1. 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

Trusted and free

Price Alerts

Price Alerts

Find the cheapest flights from St. Louis to Ontario

Cheap round-trip flights

Cheap one-way flights

Cheap last-minute flights

Cheap direct flights

United Airlines flights from St. Louis to Region of Ontario

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

American Airlines flights from St. Louis to Region of Ontario

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

momondo Fare Finder

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

See travel insights to Ontario from

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$ 580. The most expensive day to fly to Region of Ontario is Wednesday, with ticket prices averaging around C$ 899.

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 8% 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?

Alaska Airlines and American Airlines 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 December 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 4:00p.m., with 100% of daily flights taking off in the afternoon.

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

As of December 2025, there are 14 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.

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

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