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

Air Canada, Delta, and United 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 June 2026, 6 flights take off from St. Louis and land in Region of Ontario each day. The most common flight departure time for this route is 8:00a.m., with 50% of daily flights taking off at noon.

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 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 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$ 254 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.

7:03 p.m. - 6:39 a.m.

STL

YYZ

10h 36m

1 stop

3:50 p.m. - 6:15 p.m.

YYZ

STL

27h 25m

2 stops

C$ 584Multiple Airlines

Wed, 8 Jul - Wed, 15 Jul

12:11 p.m. - 6:39 a.m.

STL

YYZ

17h 28m

1 stop

4:45 p.m. - 6:36 p.m.

YYZ

STL

26h 51m

2 stops

C$ 599Multiple Airlines

Thu, 2 Jul - Sun, 5 Jul

6:58 p.m. - 6:39 a.m.

STL

YYZ

10h 41m

1 stop

4:45 p.m. - 6:36 p.m.

YYZ

STL

26h 51m

2 stops

C$ 605Multiple Airlines

Wed, 19 Aug - Sun, 23 Aug

5:33 p.m. - 12:00 p.m.

STL

YYZ

17h 27m

2 stops

7:00 a.m. - 7:36 p.m.

YYZ

STL

13h 36m

1 stop

C$ 606Multiple Airlines

Fri, 28 Aug - Mon, 31 Aug

6:34 p.m. - 12:00 p.m.

STL

YYZ

16h 26m

2 stops

8:35 p.m. - 6:15 p.m.

YYZ

STL

22h 40m

1 stop

C$ 609Multiple Airlines

Tue, 14 Jul - Wed, 22 Jul

12:10 p.m. - 3:42 p.m.

STL

YUL

2h 32mdirect

4:55 p.m. - 6:42 p.m.

YUL

STL

2h 47mdirect

C$ 705Air Canada

Sat, 4 Jul - Fri, 10 Jul

12:10 p.m. - 3:42 p.m.

STL

YUL

2h 32mdirect

3:30 p.m. - 8:07 p.m.

YUL

STL

5h 37m

1 stop

C$ 717Air Canada

Sat, 4 Jul - Fri, 10 Jul

8:55 a.m. - 3:22 p.m.

STL

YUL

5h 27m

1 stop

2:10 p.m. - 8:07 p.m.

YUL

STL

6h 57m

1 stop

C$ 728Air Canada

Sat, 4 Jul - Fri, 10 Jul

5:00 a.m. - 4:53 p.m.

STL

YUL

10h 53m

1 stop

12:31 p.m. - 8:44 p.m.

YUL

STL

9h 13m

1 stop

C$ 743American Airlines

Wed, 16 Sep - Wed, 23 Sep

2:40 p.m. - 9:40 p.m.

STL

YXU

6h 00m

1 stop

10:05 a.m. - 2:00 p.m.

YXU

STL

4h 55m

1 stop

C$ 1,036Air Canada

Tue, 8 Sep - Wed, 9 Sep

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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

25 Jun

STL2:15 p.m.Lambert-St Louis

1h 51m

YYZ5:06 p.m.Toronto Pearson Intl

28 Jun

YYZ11:15 a.m.Toronto Pearson Intl

2h 06m

STL12:21 p.m.Lambert-St Louis

C$ 689

Air Canada

4 Jul

STL12:10 p.m.Lambert-St Louis

2h 32m

YUL3:42 p.m.Montreal Pierre Elliott Trudeau Intl

10 Jul

YUL4:55 p.m.Montreal Pierre Elliott Trudeau Intl

2h 47m

STL6:42 p.m.Lambert-St Louis

C$ 705

Air Canada

25 Jun

STL8:40 a.m.Lambert-St Louis

1h 57m

YYZ11:37 a.m.Toronto Pearson Intl

28 Jun

YYZ11:15 a.m.Toronto Pearson Intl

2h 06m

STL12:21 p.m.Lambert-St Louis

C$ 707

Delta flights from St. Louis to Region of Ontario

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

Delta

13 Sep

STL1:30 p.m.Lambert-St Louis

9h 26m

1 stop

YUL11:56 p.m.Montreal Pierre Elliott Trudeau Intl

21 Sep

YUL7:43 p.m.Montreal Pierre Elliott Trudeau Intl

17h 00m

1 stop

STL11:43 a.m.Lambert-St Louis

C$ 828

Delta

1 Aug

STL6:04 p.m.Lambert-St Louis

4h 21m

1 stop

YUL11:25 p.m.Montreal Pierre Elliott Trudeau Intl

12 Aug

YUL9:30 a.m.Montreal Pierre Elliott Trudeau Intl

12h 01m

1 stop

STL8:31 p.m.Lambert-St Louis

C$ 835

Delta

16 Sep

STL6:40 a.m.Lambert-St Louis

11h 13m

2 stops

YUL6:53 p.m.Montreal Pierre Elliott Trudeau Intl

22 Sep

YUL9:30 a.m.Montreal Pierre Elliott Trudeau Intl

11h 36m

1 stop

STL8:06 p.m.Lambert-St Louis

C$ 859

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Wed 8/7

7:03 p.m.-6:39 a.m.

1 stop10h 36m

Toronto Pearson Intl

Wed 15/7

3:50 p.m.-6:15 p.m.

2 stops27h 25m

C$ 584

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Thu 2/7

12:11 p.m.-6:39 a.m.

1 stop17h 28m

Toronto Pearson Intl

Sun 5/7

4:45 p.m.-6:36 p.m.

2 stops26h 51m

C$ 599

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Wed 19/8

6:58 p.m.-6:39 a.m.

1 stop10h 41m

Toronto Pearson Intl

Sun 23/8

4:45 p.m.-6:36 p.m.

2 stops26h 51m

C$ 605

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Fri 28/8

5:33 p.m.-12:00 p.m.

2 stops17h 27m

Toronto Pearson Intl

Mon 31/8

7:00 a.m.-7:36 p.m.

1 stop13h 36m

C$ 606

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 14/7

6:34 p.m.-12:00 p.m.

2 stops16h 26m

Toronto Pearson Intl

Wed 22/7

8:35 p.m.-6:15 p.m.

1 stop22h 40m

C$ 609

Quickest round-trip

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 4/7

12:10 p.m.-3:42 p.m.

Nonstop2h 32m

Montreal Pierre Elliott Trudeau Intl

Fri 10/7

4:55 p.m.-6:42 p.m.

Nonstop2h 47m

C$ 705

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 4/7

12:10 p.m.-3:42 p.m.

Nonstop2h 32m

Montreal Pierre Elliott Trudeau Intl

Fri 10/7

3:30 p.m.-8:07 p.m.

1 stop5h 37m

C$ 717

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 4/7

8:55 a.m.-3:22 p.m.

1 stop5h 27m

Montreal Pierre Elliott Trudeau Intl

Fri 10/7

2:10 p.m.-8:07 p.m.

1 stop6h 57m

C$ 728

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 16/9

5:00 a.m.-4:53 p.m.

1 stop10h 53m

Montreal Pierre Elliott Trudeau Intl

Wed 23/9

12:31 p.m.-8:44 p.m.

1 stop9h 13m

C$ 743

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Tue 8/9

2:40 p.m.-9:40 p.m.

1 stop6h 00m

London

Wed 9/9

10:05 a.m.-2:00 p.m.

1 stop4h 55m

C$ 1,036

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, July 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$ 194. If you are unable to visit Region of Ontario during the month of July, then departing from St. Louis during the month June is also very affordable. Most momondo users find prices during this month for around C$ 194.

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 Sunday. Travellers who choose to depart for Region of Ontario on a Sunday will often find tickets for as low as C$ 474. The most expensive day to fly to Region of Ontario is Thursday, with ticket prices averaging around C$ 1,029.

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 in the afternoon. Flights from St. Louis to Region of Ontario during this time can be as low as C$ 651. If you have a flexible travel schedule, then try to avoid flying at noon when prices are C$ 800 on average. Flights to Region of Ontario from St. Louis at noon 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

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

There is only 1 cabin class 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 27% 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$ 608
Fastest flight time	1h 51m
Direct flights	Every day
Airports in Region of Ontario	125 airports

The best flight deal from St. Louis to Region of Ontario found on momondo in the last 72 hours is C$ 608

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 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 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 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 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 C$ 331	Free Cancellation	Rating 7.1 11,163 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.

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Popular Cities in Ontario

Flights to Torontofrom C$ 140

Flights to Vancouverfrom C$ 109

Flights to Montrealfrom C$ 272

Flights to Calgaryfrom C$ 140

Flights to Winnipegfrom C$ 148

Flights to Ottawafrom C$ 270

Flights to Halifaxfrom C$ 169

Flights to Kelownafrom C$ 130

Flights to Saskatoonfrom C$ 226

Flights to Reginafrom C$ 246

Flights to St. John'sfrom C$ 272

Flights to Québec Cityfrom C$ 321

Cheap flights from St. Louis to Ontario from C$ 254

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 24/7. 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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Air Canada flights from St. Louis to Region of Ontario

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

Delta flights from St. Louis to Region of Ontario

Our best Delta 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?

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

St. Louis flight routes

According to popular flight searches on momondo this year

Region of Ontario flight routes

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