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

Flight times vary depending on what airport in Region of Ontario you fly out of and what airport in St. Louis you fly into. For example, flying from Toronto to St. Louis takes 2h 05m on average. On the other hand, flying from Ottawa to St. Louis takes 6h 01m on average. Keep in mind that it’s always quicker to opt for a non-stop flight, so be sure to check momondo to see if there are any available for your route.

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 28 per week as of September 2026. The most frequent departure day is Mon, with 14% of weekly flights leaving on this day.

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

American Airlines and United Airlines 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?

4 flights are operational daily from Region of Ontario to St. Louis as of September 2026. The most popular departure time for this route is 12:00p.m., with 50% of flights per day taking off in the afternoon.

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 are refreshed on a daily basis.

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

The number of operators available for flights from Ontario to Lambert-St Louis Airport is 2 as of September 2026.

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

The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to 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 you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

C$ 251 Cheap Flights from Ontario to St. Louis in 2026/27

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Ontario to St. Louis

Round-trip

One-way

Last minute

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Cheap round-trip flights

Enter your travel dates to find the best prices.

7:29 a.m. - 4:53 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

10h 24m1 stop Chicago O'Hare Intl

7:28 a.m. - 5:44 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

9h 16m1 stop Chicago O'Hare Intl

C$ 448American Airlines

Tue, 20 Oct - Tue, 27 Oct

11:39 a.m. - 12:19 a.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

13h 40m1 stop Chicago O'Hare Intl

5:01 a.m. - 5:41 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

11h 40m1 stop Chicago O'Hare Intl

C$ 448American Airlines

Sat, 24 Oct - Sat, 14 Nov

11:36 a.m. - 7:22 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

8h 46m1 stop Chicago O'Hare Intl

6:00 a.m. - 5:41 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

10h 41m1 stop Chicago O'Hare Intl

C$ 448American Airlines

Mon, 2 Nov - Mon, 9 Nov

7:29 a.m. - 4:53 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

10h 24m1 stop Chicago O'Hare Intl

5:00 a.m. - 5:44 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

11h 44m1 stop Chicago O'Hare Intl

C$ 448American Airlines

Tue, 20 Oct - Sat, 31 Oct

9:00 p.m. - 3:43 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

19h 43m1 stop Chicago O'Hare Intl

5:36 p.m. - 9:54 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

15h 18m1 stop Chicago O'Hare Intl

C$ 661United Airlines

Fri, 16 Oct - Mon, 19 Oct

5:15 p.m. - 3:43 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

23h 28m1 stop Chicago O'Hare Intl

1:29 p.m. - 11:26 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

8h 57m1 stop Chicago O'Hare Intl

C$ 661United Airlines

Fri, 16 Oct - Mon, 19 Oct

6:55 p.m. - 12:10 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

18h 15m1 stop Chicago O'Hare Intl

7:30 a.m. - 7:10 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

10h 40m1 stop Chicago O'Hare Intl

C$ 662United Airlines

Sun, 8 Nov - Sat, 14 Nov

12:55 p.m. - 2:00 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 827Air Canada

Thu, 15 Oct - Sun, 18 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 830Air Canada

Thu, 15 Oct - Sun, 18 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

2:40 p.m. - 5:34 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 830Air Canada

Sat, 10 Oct - Sun, 11 Oct

Cheap last-minute flights

Enter your travel dates to find the best prices.

12:55 p.m. - 2:00 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

2:40 p.m. - 5:34 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 845Air Canada

Wed, 30 Sep - Sat, 3 Oct

7:15 p.m. - 12:27 a.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

6h 12m1 stop Chicago O'Hare Intl

7:27 a.m. - 11:26 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

14h 59m1 stop Chicago O'Hare Intl

C$ 976Multiple Airlines

Fri, 25 Sep - Sat, 26 Sep

9:45 a.m. - 1:06 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

4h 21m1 stop Detroit Metropolitan Wayne County

2:00 p.m. - 9:55 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

30h 55m2 stops Jonesboro Nashville Intl

C$ 1,029Multiple Airlines

Tue, 29 Sep - Wed, 30 Sep

7:20 a.m. - 1:10 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

30h 50m2 stops New York LaGuardia Atlanta Hartsfield-Jackson

4:30 p.m. - 1:45 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

20h 15m1 stop Orlando

C$ 1,048Multiple Airlines

Sun, 27 Sep - Fri, 23 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

2:56 p.m. - 8:44 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

4h 48m1 stop Chicago O'Hare Intl

C$ 1,140United Airlines

Wed, 30 Sep - Sat, 3 Oct

12:55 p.m. - 2:00 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

1:36 p.m. - 11:16 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

8h 40m1 stop Denver Intl

C$ 1,140United Airlines

Sat, 26 Sep - Sat, 3 Oct

5:15 p.m. - 9:21 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

5h 06m1 stop Chicago O'Hare Intl

9:04 a.m. - 5:56 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

7h 52m1 stop Chicago O'Hare Intl

C$ 1,213United Airlines

Wed, 30 Sep - Sat, 3 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,415Air Canada

Sun, 27 Sep - Fri, 23 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,455Air Canada

Sun, 27 Sep - Fri, 23 Oct

10:15 a.m. - 3:43 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

6h 28m1 stop Chicago O'Hare Intl

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,567Air Canada

Mon, 28 Sep - Wed, 30 Sep

Cheap direct flights

Enter your travel dates to find the best prices.

12:55 p.m. - 2:00 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 827Air Canada

Thu, 15 Oct - Sun, 18 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

2:40 p.m. - 5:34 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 830Air Canada

Sat, 10 Oct - Sun, 11 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 830Air Canada

Thu, 15 Oct - Sun, 18 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

4:05 p.m. - 6:59 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 852Air Canada

Wed, 21 Oct - Wed, 28 Oct

12:55 p.m. - 2:00 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

2:40 p.m. - 5:34 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 985United Airlines

Thu, 15 Oct - Sun, 18 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

4:05 p.m. - 6:59 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,030United Airlines

Wed, 21 Oct - Wed, 28 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

8:55 a.m. - 11:49 a.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,033Multiple Airlines

Thu, 8 Oct - Sat, 10 Oct

7:15 p.m. - 8:20 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

4:05 p.m. - 6:59 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,034United Airlines

Tue, 20 Oct - Tue, 27 Oct

12:55 p.m. - 2:00 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

2:40 p.m. - 5:34 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,137Multiple Airlines

Fri, 9 Oct - Sun, 11 Oct

12:55 p.m. - 2:00 p.m.YYZ Toronto Pearson Intl-STL Lambert-St Louis

2h 05mdirect

2:40 p.m. - 5:34 p.m.STL Lambert-St Louis-YYZ Toronto Pearson Intl

1h 54mdirect

C$ 1,160Multiple Airlines

Fri, 9 Oct - Sun, 11 Oct

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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

16 Oct

YYZ9:00 p.m.Toronto Pearson Intl

19h 43m

1 stop

STL3:43 p.m.Lambert-St Louis

19 Oct

STL5:36 p.m.Lambert-St Louis

15h 18m

1 stop

YYZ9:54 a.m.Toronto Pearson Intl

C$ 661

United Airlines

8 Nov

YYZ6:55 p.m.Toronto Pearson Intl

18h 15m

1 stop

STL12:10 p.m.Lambert-St Louis

14 Nov

STL7:30 a.m.Lambert-St Louis

10h 40m

1 stop

YYZ7:10 p.m.Toronto Pearson Intl

C$ 662

United Airlines

16 Oct

YYZ9:00 p.m.Toronto Pearson Intl

19h 43m

1 stop

STL3:43 p.m.Lambert-St Louis

19 Oct

STL5:36 p.m.Lambert-St Louis

15h 18m

1 stop

YYZ9:54 a.m.Toronto Pearson Intl

C$ 664

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

15 Oct

YOW2:50 p.m.Ottawa

4h 51m

1 stop

STL6:41 p.m.Lambert-St Louis

19 Oct

STL2:40 p.m.Lambert-St Louis

5h 40m

1 stop

YOW9:20 p.m.Ottawa

C$ 841

Air Canada

30 Sep

YYZ12:55 p.m.Toronto Pearson Intl

2h 05m

STL2:00 p.m.Lambert-St Louis

3 Oct

STL2:40 p.m.Lambert-St Louis

1h 54m

YYZ5:34 p.m.Toronto Pearson Intl

C$ 845

Air Canada

16 Oct

YOW2:50 p.m.Ottawa

4h 51m

1 stop

STL6:41 p.m.Lambert-St Louis

26 Oct

STL4:05 p.m.Lambert-St Louis

6h 50m

1 stop

YOW11:55 p.m.Ottawa

C$ 851

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Tue 20/10

7:29 a.m.-4:53 p.m.

1 stop10h 24m

Lambert-St Louis

Tue 27/10

7:28 a.m.-5:44 p.m.

1 stop9h 16m

C$ 448

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Sat 24/10

11:39 a.m.-12:19 a.m.

1 stop13h 40m

Lambert-St Louis

Sat 14/11

5:01 a.m.-5:41 p.m.

1 stop11h 40m

C$ 448

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Mon 2/11

11:36 a.m.-7:22 p.m.

1 stop8h 46m

Lambert-St Louis

Mon 9/11

6:00 a.m.-5:41 p.m.

1 stop10h 41m

C$ 448

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Tue 20/10

7:29 a.m.-4:53 p.m.

1 stop10h 24m

Lambert-St Louis

Sat 31/10

5:00 a.m.-5:44 p.m.

1 stop11h 44m

C$ 448

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Fri 16/10

9:00 p.m.-3:43 p.m.

1 stop19h 43m

Lambert-St Louis

Mon 19/10

5:36 p.m.-9:54 a.m.

1 stop15h 18m

C$ 661

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Fri 16/10

5:15 p.m.-3:43 p.m.

1 stop23h 28m

Lambert-St Louis

Mon 19/10

1:29 p.m.-11:26 p.m.

1 stop8h 57m

C$ 661

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Sun 8/11

6:55 p.m.-12:10 p.m.

1 stop18h 15m

Lambert-St Louis

Sat 14/11

7:30 a.m.-7:10 p.m.

1 stop10h 40m

C$ 662

Quickest round-trip

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Thu 15/10

12:55 p.m.-2:00 p.m.

Nonstop2h 05m

Lambert-St Louis

Sun 18/10

8:55 a.m.-11:49 a.m.

Nonstop1h 54m

C$ 827

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Thu 15/10

7:15 p.m.-8:20 p.m.

Nonstop2h 05m

Lambert-St Louis

Sun 18/10

8:55 a.m.-11:49 a.m.

Nonstop1h 54m

C$ 830

TorontoSt. Louis

YYZ Toronto Pearson Intl - STL Lambert-St Louis

YYZSTL

Toronto Pearson Intl

Sat 10/10

7:15 p.m.-8:20 p.m.

Nonstop2h 05m

Lambert-St Louis

Sun 11/10

2:40 p.m.-5:34 p.m.

Nonstop1h 54m

C$ 830

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 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

Airlines

Other information

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

The month of January is, on average, the cheapest month to fly to St. Louis from Region of Ontario, with most prices found around C$ 589. If you don’t want to visit St. Louis in January, then you should wait until February to fly from Region of Ontario, when ticket prices are also cheap, with an average price of C$ 602.

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

Our data shows that Saturday is the least expensive day to fly to St. Louis. Tickets to fly out on this day can be as low as C$ 597. The most expensive day to fly to St. Louis is Monday, with ticket prices averaging around C$ 857.

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

The cheapest time of day to fly to St. Louis is in the morning when flights can be purchased for as low as C$ 671. If you have a flexible travel schedule, then try to avoid flying in the evening when prices are C$ 1,018 on average. Flights to St. Louis from Region of Ontario in the evening are generally more expensive because this time of day is more convenient for travellers’ schedules.

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 from Ontario 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 C$ 734 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 C$ 506 on momondo.

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

There are 3 cabin classes available to choose from on Region of Ontario to 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?

No. A direct flight is the cheapest option for a flight between Region of Ontario 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	C$ 251
Fastest flight time	2h 05m
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 C$ 251. The best round-trip flight deal from Region of Ontario to St. Louis found on momondo in the last 72 hours is C$ 448.

The fastest flight from Region of Ontario to St. Louis takes 2h 05m

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

There is 1 airport in St. Louis. From Region of Ontario there are direct flights to Lambert-St Louis (STL).

Search flight deals

Frequently asked questions about flying from Ontario to St. Louis

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 are refreshed on a daily basis.
How many operators does momondo search for flights from Ontario to Lambert-St Louis Airport?
The number of operators available for flights from Ontario to Lambert-St Louis Airport is 2 as of September 2026.
How old do you have to be to fly from Ontario to Lambert-St Louis Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to 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 you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Region of Ontario to St. Louis?
momondo data reveals that the most frequently booked plane model on the route from Region of Ontario to St. Louis is Canadair (Bombardier) Regional Jet 900, representing 56.86% of all bookings. The subsequent popular models are Embraer 175 at 40.20%, Airbus A220-300 at 1.96%, and Airbus A220 at 0.98%.

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 C$ 339	Free Cancellation	Rating 7.1 11,676 reviews		Search Air Canada flights
United Airlines	PriceFrom C$ 345	Free Cancellation	Rating 7.4 10,233 reviews		Search United Airlines flights

St. Charles

Why use momondo?

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

It is quick and easy to find Ontario to St. Louis flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to St. Louis that suits you.

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 you have performed a search for Ontario to St. Louis flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

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

Yes momondo offers price alerts on flights to St. Louis from Ontario. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

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Cheap flights from Ontario to St. Louis from C$ 251

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 3/11. 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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United Airlines flights from Region of Ontario to St. Louis

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

Air Canada flights from Region of Ontario to St. Louis

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

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

See travel insights to St. Louis from

How to get the cheapest flight ticket from Region of Ontario to St. Louis

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?

How far in advance should I book a flight from Ontario to St. Louis?

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

Can stopping save me money on Region of Ontario to St. Louis flights?

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

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

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

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

Cheap Region of Ontario to St. Louis flight deals and tips

Best price found

Fastest flight time

Direct flights

Airports in St. Louis

Frequently asked questions about flying from 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

Travelling to a place near St. Louis?

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