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

American Airlines is the most popular carrier operating from Montreal to Lambert-St Louis

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

Prices for flights from Montreal to Lambert-St Louis Airport are updated daily.

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

There is 1 operator available for flights from Montreal to Lambert-St Louis Airport as of November 2026.

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

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Montreal 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$ 402 Cheap Flights from Montreal to St. Louis in 2026/27

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Montreal to St. Louis

Round-trip

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Cheap round-trip flights

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12:08 p.m. - 7:58 p.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

8h 50m1 stop Chicago O'Hare Intl

8:24 p.m. - 11:28 a.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

14h 04m1 stop Chicago O'Hare Intl

C$ 604American Airlines

Thu, 3 Dec - Mon, 7 Dec

12:08 p.m. - 7:58 p.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

8h 50m1 stop Chicago O'Hare Intl

8:24 p.m. - 11:28 a.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

14h 04m1 stop Chicago O'Hare Intl

C$ 613American Airlines

Thu, 3 Dec - Mon, 7 Dec

6:45 a.m. - 11:17 a.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

29h 32m3 stops Toronto Pearson Intl Fort Lauderdale Atlanta Hartsfield-Jackson

12:02 p.m. - 4:00 p.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

26h 58m3 stops Atlanta Hartsfield-Jackson Newark Toronto Island

C$ 634Multiple Airlines

Thu, 3 Dec - Mon, 7 Dec

12:08 p.m. - 7:58 p.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

8h 50m1 stop Chicago O'Hare Intl

8:24 p.m. - 11:28 a.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

14h 04m1 stop Chicago O'Hare Intl

C$ 636American Airlines

Thu, 3 Dec - Mon, 7 Dec

6:45 a.m. - 11:17 a.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

29h 32m3 stops Toronto Pearson Intl Fort Lauderdale Atlanta Hartsfield-Jackson

12:02 p.m. - 4:00 p.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

26h 58m3 stops Atlanta Hartsfield-Jackson Newark Toronto Island

C$ 699Multiple Airlines

Thu, 3 Dec - Mon, 7 Dec

6:25 p.m. - 11:17 a.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

17h 52m2 stops Washington, D.C. Dulles Intl Atlanta Hartsfield-Jackson

12:02 p.m. - 8:32 a.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

19h 30m2 stops Atlanta Hartsfield-Jackson Newark

C$ 720Multiple Airlines

Thu, 3 Dec - Mon, 7 Dec

4:40 p.m. - 11:17 a.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

19h 37m3 stops Toronto Island Newark Atlanta Hartsfield-Jackson

12:02 p.m. - 7:12 p.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

30h 10m3 stops Atlanta Hartsfield-Jackson Fort Lauderdale Toronto Pearson Intl

C$ 742Multiple Airlines

Thu, 3 Dec - Mon, 7 Dec

6:25 p.m. - 11:17 a.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

17h 52m2 stops Washington, D.C. Dulles Intl Atlanta Hartsfield-Jackson

12:02 p.m. - 7:46 a.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

18h 44m2 stops Atlanta Hartsfield-Jackson Baltimore/Washington

C$ 756Multiple Airlines

Thu, 3 Dec - Mon, 7 Dec

9:10 a.m. - 3:26 p.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

7h 16m1 stop Toronto Pearson Intl

4:05 p.m. - 12:25 a.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

7h 20m1 stop Toronto Pearson Intl

C$ 1,006Air Canada

Thu, 19 Nov - Sat, 21 Nov

10:10 a.m. - 3:26 p.m.YUL Montreal Pierre Elliott Trudeau Intl-STL Lambert-St Louis

6h 16m1 stop Toronto Pearson Intl

4:05 p.m. - 12:25 a.m.STL Lambert-St Louis-YUL Montreal Pierre Elliott Trudeau Intl

7h 20m1 stop Toronto Pearson Intl

C$ 1,006Air Canada

Fri, 20 Nov - Sat, 21 Nov

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Delta flights from Montreal to St. Louis

Our best Delta deals on Montreal to St. Louis flight tickets

Delta

3 Dec

YUL9:40 a.m.Montreal Pierre Elliott Trudeau Intl

11h 52m

2 stops

STL8:32 p.m.Lambert-St Louis

7 Dec

STL2:33 p.m.Lambert-St Louis

8h 15m

1 stop

YUL11:48 p.m.Montreal Pierre Elliott Trudeau Intl

C$ 1,047

Delta

19 Nov

YUL4:50 p.m.Montreal Pierre Elliott Trudeau Intl

4h 39m

1 stop

STL8:29 p.m.Lambert-St Louis

21 Nov

STL8:00 a.m.Lambert-St Louis

23h 34m

1 stop

YUL8:34 a.m.Montreal Pierre Elliott Trudeau Intl

C$ 1,279

Delta

3 Dec

YUL9:40 a.m.Montreal Pierre Elliott Trudeau Intl

11h 52m

2 stops

STL8:32 p.m.Lambert-St Louis

7 Dec

STL6:32 a.m.Lambert-St Louis

11h 22m

2 stops

YUL6:54 p.m.Montreal Pierre Elliott Trudeau Intl

C$ 1,293

United Airlines flights from Montreal to St. Louis

Our best United Airlines deals on Montreal to St. Louis flight tickets

United Airlines

2 Feb

YUL1:10 p.m.Montreal Pierre Elliott Trudeau Intl

9h 27m

1 stop

STL9:37 p.m.Lambert-St Louis

3 Feb

STL7:29 a.m.Lambert-St Louis

10h 28m

1 stop

YUL6:57 p.m.Montreal Pierre Elliott Trudeau Intl

C$ 866

United Airlines

29 Jan

YUL9:25 a.m.Montreal Pierre Elliott Trudeau Intl

8h 48m

1 stop

STL5:13 p.m.Lambert-St Louis

2 Feb

STL5:00 a.m.Lambert-St Louis

11h 07m

1 stop

YUL5:07 p.m.Montreal Pierre Elliott Trudeau Intl

C$ 876

United Airlines

16 Dec

YUL9:25 a.m.Montreal Pierre Elliott Trudeau Intl

8h 40m

1 stop

STL5:05 p.m.Lambert-St Louis

23 Dec

STL8:05 a.m.Lambert-St Louis

10h 02m

1 stop

YUL7:07 p.m.Montreal Pierre Elliott Trudeau Intl

C$ 887

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

12:08 p.m.-7:58 p.m.

1 stop8h 50m

Lambert-St Louis

Mon 7/12

8:24 p.m.-11:28 a.m.

1 stop14h 04m

C$ 604

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

12:08 p.m.-7:58 p.m.

1 stop8h 50m

Lambert-St Louis

Mon 7/12

8:24 p.m.-11:28 a.m.

1 stop14h 04m

C$ 613

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

6:45 a.m.-11:17 a.m.

3 stops29h 32m

Lambert-St Louis

Mon 7/12

12:02 p.m.-4:00 p.m.

3 stops26h 58m

C$ 634

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

12:08 p.m.-7:58 p.m.

1 stop8h 50m

Lambert-St Louis

Mon 7/12

8:24 p.m.-11:28 a.m.

1 stop14h 04m

C$ 636

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

6:45 a.m.-11:17 a.m.

3 stops29h 32m

Lambert-St Louis

Mon 7/12

12:02 p.m.-4:00 p.m.

3 stops26h 58m

C$ 699

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

6:25 p.m.-11:17 a.m.

2 stops17h 52m

Lambert-St Louis

Mon 7/12

12:02 p.m.-8:32 a.m.

2 stops19h 30m

C$ 720

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

4:40 p.m.-11:17 a.m.

3 stops19h 37m

Lambert-St Louis

Mon 7/12

12:02 p.m.-7:12 p.m.

3 stops30h 10m

C$ 742

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 3/12

6:25 p.m.-11:17 a.m.

2 stops17h 52m

Lambert-St Louis

Mon 7/12

12:02 p.m.-7:46 a.m.

2 stops18h 44m

C$ 756

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 19/11

9:10 a.m.-3:26 p.m.

1 stop7h 16m

Lambert-St Louis

Sat 21/11

4:05 p.m.-12:25 a.m.

1 stop7h 20m

C$ 1,006

Quickest round-trip

MontrealSt. Louis

YUL Montreal Pierre Elliott Trudeau Intl - STL Lambert-St Louis

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 20/11

10:10 a.m.-3:26 p.m.

1 stop6h 16m

Lambert-St Louis

Sat 21/11

4:05 p.m.-12:25 a.m.

1 stop7h 20m

C$ 1,006

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 Montreal 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

What is the typical price of a round-trip flight between Montreal and St. Louis?

Prices are currently low for flights on this route.

Typical prices usually range from C$ 780 to C$ 892.
The lowest price recently found on this route was C$ 604.

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

The month of August is, on average, the cheapest month to fly to St. Louis from Montreal, with most prices found around C$ 618. If you don’t want to visit St. Louis in August, then you should wait until May to fly from Montreal, when ticket prices are also cheap, with an average price of C$ 766.

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

Our data shows that Friday is the least expensive day to fly to St. Louis. Tickets to fly out on this day can be as low as C$ 776. The most expensive day to fly to St. Louis is Tuesday, with ticket prices averaging around C$ 1,674.

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 afternoon when flights can be purchased for as low as C$ 790. If you have a flexible travel schedule, then try to avoid flying in the morning when prices are C$ 1,674 on average. Flights to St. Louis from Montreal in the morning are generally more expensive because this time of day is more convenient for travellers’ schedules.

What is the cheapest Montreal to Lambert-St Louis flight route?

Fly from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis for the best Montreal - Lambert-St Louis flight prices

What cabin class options are available on Montreal to St. Louis flights?

There is only 1 cabin class available to choose from on Montreal 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 Montreal to St. Louis flights?

You could potentially save up to 44% on your flight if you consider stops on a Montreal to St. Louis flight.

When to book flights from Montreal to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Montreal to St. Louis according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Montreal to St. Louis (YMQ to STL) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Montreal to St. Louis

Best price found	C$ 402
Fastest flight time	8h 48m
Direct flights	None

The best one-way flight to St. Louis from Montreal in the past 72 hours is C$ 402. The best round-trip flight deal from Montreal to St. Louis found on momondo in the last 72 hours is C$ 604.

The fastest flight from Montreal to St. Louis takes 8h 48m

There are no direct flights from Montreal to St. Louis. There are no popular flight routes from Montreal to St. Louis.

Search flight deals

Frequently asked questions about flying from Montreal to St. Louis

How far is Montreal to Lambert-St Louis by plane?
The straight-line distance from Montreal to Lambert-St Louis is 1566.0 km. Flights usually cover this in 8h 48m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from Montreal to Lambert-St Louis Airport?
Prices for flights from Montreal to Lambert-St Louis Airport are updated daily.
How many operators does momondo search for flights from Montreal to Lambert-St Louis Airport?
There is 1 operator available for flights from Montreal to Lambert-St Louis Airport as of November 2026.
How old do you have to be to fly from Montreal to Lambert-St Louis Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Montreal 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 Montreal to St. Louis?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Montreal to St. Louis is Canadair (Bombardier) Regional Jet 900 (72.73% of total bookings). The next most popular plane models are Embraer 175 (22.73%) and Airbus A220-300 (4.55%).
What is the most popular airline from Montreal to St. Louis?
Based on momondo bookings for flights between Montreal and St. Louis, the leading airline is Air Canada, making up 100% of the total bookings.

Best airlines flying from Montreal to St. Louis

Compare and see reviews for airlines that fly from Montreal to St. Louis with momondo

Airline	Rating	Free Cancellation	Price
Air Canada	PriceFrom C$ 563	Free Cancellation	Rating 7.1 11,862 reviews		Search Air Canada flights

St. Charles

Why use momondo?

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

It is quick and easy to find Montreal 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 Montreal to St. Louis with flexible booking policies on momondo?

Yes. All flights to St. Louis from Montreal on momondo can be compared and filtered by various policies on offer, including flexible booking.

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

Once all potential Montreal to St. Louis flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

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

If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Montreal and alert you when they change.

An easier way to manage your St. Louis trip

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Cheap flights from Montreal to St. Louis from C$ 402

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Montreal to St. Louis departing on 16/1. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Delta flights from Montreal to St. Louis

Our best Delta deals on Montreal to St. Louis flight tickets

United Airlines flights from Montreal to St. Louis

Our best United Airlines deals on Montreal to St. Louis flight tickets

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See travel insights to St. Louis from

How to get the cheapest flight ticket from Montreal to St. Louis

What is the typical price of a round-trip flight between Montreal and 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 Montreal to Lambert-St Louis flight route?

What cabin class options are available on Montreal to St. Louis flights?

Can stopping save me money on Montreal to St. Louis flights?

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

When to book flights from Montreal to St. Louis

Cheap Montreal to St. Louis (YMQ to STL) flight deals and tips

Best price found

Fastest flight time

Direct flights

Frequently asked questions about flying from Montreal to St. Louis

Best airlines flying from Montreal to St. Louis

Compare and see reviews for airlines that fly from Montreal to St. Louis with momondo

Travelling to a place near St. Louis?

Why use momondo?

An easier way to manage your St. Louis 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 the United States

Airports servicing Missouri

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