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

As of March 2026, 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 March 2026, 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?

American Airlines, Air Canada, and United 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 March 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$ 175 Cheap Flights from St. Louis to Ontario in 2026

1 adult

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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.

7:05 a.m. - 6:33 p.m.

STL

YYZ

10h 28m

1 stop

1:15 p.m. - 10:17 p.m.

YYZ

STL

10h 02m

1 stop

C$ 455American Airlines

Tue, 14 Apr - Wed, 15 Apr

9:55 p.m. - 6:43 a.m.

STL

YYZ

31h 48m

1 stop

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

YYZ

STL

26h 51m

2 stops

C$ 471Multiple Airlines

Sun, 19 Apr - Sun, 26 Apr

4:59 p.m. - 12:30 a.m.

STL

YUL

30h 31m

1 stop

8:00 a.m. - 6:50 a.m.

YUL

STL

47h 50m

2 stops

C$ 497Multiple Airlines

Mon, 20 Apr - Mon, 27 Apr

8:03 p.m. - 11:44 a.m.

STL

YUL

14h 41m

1 stop

12:30 p.m. - 8:09 p.m.

YUL

STL

8h 39m

1 stop

C$ 506American Airlines

Wed, 8 Apr - Sat, 11 Apr

4:59 p.m. - 12:30 a.m.

STL

YUL

30h 31m

1 stop

8:00 a.m. - 6:50 a.m.

YUL

STL

47h 50m

2 stops

C$ 507Multiple Airlines

Mon, 20 Apr - Mon, 27 Apr

9:55 p.m. - 6:43 a.m.

STL

YYZ

31h 48m

1 stop

8:20 p.m. - 11:19 p.m.

YYZ

STL

27h 59m

1 stop

C$ 510Multiple Airlines

Sun, 19 Apr - Sun, 26 Apr

4:05 p.m. - 9:19 p.m.

STL

YXU

4h 14m

1 stop

12:20 p.m. - 8:25 p.m.

YXU

STL

9h 05m

2 stops

C$ 836Air Canada

Wed, 29 Apr - Sat, 2 May

4:05 p.m. - 9:19 p.m.

STL

YXU

4h 14m

1 stop

12:20 p.m. - 8:04 p.m.

YXU

STL

8h 44m

1 stop

C$ 858Air Canada

Wed, 29 Apr - Sat, 2 May

4:05 p.m. - 9:19 p.m.

STL

YXU

4h 14m

1 stop

12:20 p.m. - 8:25 p.m.

YXU

STL

9h 05m

2 stops

C$ 909Air Canada

Wed, 29 Apr - Sat, 2 May

4:05 p.m. - 9:19 p.m.

STL

YXU

4h 14m

1 stop

12:20 p.m. - 8:25 p.m.

YXU

STL

9h 05m

2 stops

C$ 924Air Canada

Wed, 29 Apr - Sat, 2 May

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 Apr

STL7:05 a.m.Lambert-St Louis

10h 28m

1 stop

YYZ6:33 p.m.Toronto Pearson Intl

15 Apr

YYZ1:15 p.m.Toronto Pearson Intl

10h 02m

1 stop

STL10:17 p.m.Lambert-St Louis

C$ 455

American Airlines

8 Apr

STL8:03 p.m.Lambert-St Louis

14h 41m

1 stop

YUL11:44 a.m.Montreal Pierre Elliott Trudeau Intl

11 Apr

YUL12:30 p.m.Montreal Pierre Elliott Trudeau Intl

8h 39m

1 stop

STL8:09 p.m.Lambert-St Louis

C$ 506

American Airlines

8 Apr

STL8:03 p.m.Lambert-St Louis

14h 41m

1 stop

YUL11:44 a.m.Montreal Pierre Elliott Trudeau Intl

11 Apr

YUL1:03 p.m.Montreal Pierre Elliott Trudeau Intl

11h 43m

2 stops

STL11:46 p.m.Lambert-St Louis

C$ 520

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

2 May

STL7:45 a.m.Lambert-St Louis

8h 45m

1 stop

YUL5:30 p.m.Montreal Pierre Elliott Trudeau Intl

4 May

YUL6:30 p.m.Montreal Pierre Elliott Trudeau Intl

2h 55m

STL8:25 p.m.Lambert-St Louis

C$ 631

Air Canada

2 May

STL7:45 a.m.Lambert-St Louis

8h 45m

1 stop

YUL5:30 p.m.Montreal Pierre Elliott Trudeau Intl

4 May

YUL7:00 a.m.Montreal Pierre Elliott Trudeau Intl

6h 06m

1 stop

STL12:06 p.m.Lambert-St Louis

C$ 642

Air Canada

19 Apr

STL4:05 p.m.Lambert-St Louis

1h 57m

YYZ7:02 p.m.Toronto Pearson Intl

26 Apr

YYZ2:10 p.m.Toronto Pearson Intl

2h 15m

STL3:25 p.m.Lambert-St Louis

C$ 664

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 14/4

7:05 a.m.-6:33 p.m.

1 stop10h 28m

Toronto Pearson Intl

Wed 15/4

1:15 p.m.-10:17 p.m.

1 stop10h 02m

C$ 455

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Sun 19/4

9:55 p.m.-6:43 a.m.

1 stop31h 48m

Toronto Pearson Intl

Sun 26/4

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

2 stops26h 51m

C$ 471

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Mon 20/4

4:59 p.m.-12:30 a.m.

1 stop30h 31m

Montreal Pierre Elliott Trudeau Intl

Mon 27/4

8:00 a.m.-6:50 a.m.

2 stops47h 50m

C$ 497

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 8/4

8:03 p.m.-11:44 a.m.

1 stop14h 41m

Montreal Pierre Elliott Trudeau Intl

Sat 11/4

12:30 p.m.-8:09 p.m.

1 stop8h 39m

C$ 506

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Mon 20/4

4:59 p.m.-12:30 a.m.

1 stop30h 31m

Montreal Pierre Elliott Trudeau Intl

Mon 27/4

8:00 a.m.-6:50 a.m.

2 stops47h 50m

C$ 507

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Sun 19/4

9:55 p.m.-6:43 a.m.

1 stop31h 48m

Toronto Pearson Intl

Sun 26/4

8:20 p.m.-11:19 p.m.

1 stop27h 59m

C$ 510

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Wed 29/4

4:05 p.m.-9:19 p.m.

1 stop4h 14m

London

Sat 2/5

12:20 p.m.-8:25 p.m.

2 stops9h 05m

C$ 836

Quickest round-trip

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Wed 29/4

4:05 p.m.-9:19 p.m.

1 stop4h 14m

London

Sat 2/5

12:20 p.m.-8:04 p.m.

1 stop8h 44m

C$ 858

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Wed 29/4

4:05 p.m.-9:19 p.m.

1 stop4h 14m

London

Sat 2/5

12:20 p.m.-8:25 p.m.

2 stops9h 05m

C$ 909

St. LouisLondon

STL - YXU

STLYXU

Lambert-St Louis

Wed 29/4

4:05 p.m.-9:19 p.m.

1 stop4h 14m

London

Sat 2/5

12:20 p.m.-8:25 p.m.

2 stops9h 05m

C$ 924

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, June 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$ 415. If you are unable to visit Region of Ontario during the month of June, then departing from St. Louis during the month March is also very affordable. Most momondo users find prices during this month for around C$ 474.

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$ 460. The most expensive day to fly to Region of Ontario is Wednesday, with ticket prices averaging around C$ 883.

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 morning. Flights from St. Louis to Region of Ontario during this time can be as low as C$ 570. If you have a flexible travel schedule, then try to avoid flying in the afternoon when prices are C$ 632 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

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 44% 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$ 321
Fastest flight time	1h 51m
Direct flights	Every day
Airports in Region of Ontario	123 airports

The best flight deal from St. Louis to Region of Ontario found on momondo in the last 72 hours is C$ 321

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 123 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

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 March 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 Embraer 175, representing 34.68% of all bookings. The subsequent popular models are Canadair (Bombardier) Regional Jet 900 at 15.32%, Boeing 787-8 Dreamliner at 15.32%, and Airbus A220-300 at 12.90%.

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$ 321	Free Cancellation	Rating 7.1 10,800 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.