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$143+ Cheap flights from St. Louis (STL) to Montreal (YMQ)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/5. Fares are subject to change and may not be available on all flights or dates of travel.
STL — YMQ
Aug 25 — Sep 11
Mon 8/25
Mon 9/1
1 adult, Economy
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Cheap flight deals from St. Louis to Montreal

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Montreal (YMQ). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated August 20, 2025.

Round-trip from

$333
(American Airlines)

One-way from

$143
(American Airlines)

Popular in

February

Cheapest in

June

Average price

$462

Good round-trip deal

$603 or less

Good one-way deal

$438 or less
From Lambert-St Louis to Montreal (YMQ)
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One-way flight from Lambert-St Louis to Montreal (YMQ)
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Highest demand for flights based on searches. 15% potential increase in price ($110 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($16 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Price to beat on a round-trip flight from Lambert-St Louis to Montreal (YMQ).
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Price to beat on a one-way flight from Lambert-St Louis to Montreal (YMQ).
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Find flight deals from St. Louis to Montreal

Cheapest flights from St. Louis to Montreal
Explore the most affordable flight options available from St. Louis to Montreal. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 20, 2025.

This American Airlines deal was found by Cheapflights users on 8/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/67:58 pmSTL - YUL
1 stop18h 13mAmerican Airlines
Sun 11/93:52 pmYUL - STL
1 stop17h 18mAmerican Airlines
Deal found 8/19$333
This American Airlines deal was found by Cheapflights users on 8/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/116:00 amSTL - YUL
2 stops15h 39mAmerican Airlines
Fri 11/143:52 pmYUL - STL
1 stop17h 18mAmerican Airlines
Deal found 8/20$346
This American Airlines deal was found by Cheapflights users on 8/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/177:23 amSTL - YUL
1 stop8h 10mAmerican Airlines
Wed 9/2412:31 pmYUL - STL
1 stop10h 22mAmerican Airlines
Deal found 8/18$348
This American Airlines deal was found by Cheapflights users on 8/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/277:23 amSTL - YUL
1 stop8h 10mAmerican Airlines
Mon 9/295:15 pmYUL - STL
1 stop23h 22mAmerican Airlines
Deal found 8/19$359
This American Airlines deal was found by Cheapflights users on 8/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/168:05 pmSTL - YUL
1 stop14h 35mAmerican Airlines
Sat 10/2512:30 pmYUL - STL
1 stop10h 36mAmerican Airlines
Deal found 8/19$374
This American Airlines deal was found by Cheapflights users on 8/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/36:10 amSTL - YUL
1 stop9h 23mAmerican Airlines
Mon 10/612:30 pmYUL - STL
1 stop8h 56mAmerican Airlines
Deal found 8/19$378
This American Airlines deal was found by Cheapflights users on 8/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/176:00 amSTL - YUL
1 stop9h 39mAmerican Airlines
Sat 10/257:50 amYUL - STL
2 stops11h 21mAmerican Airlines
Deal found 8/20$388
This United Airlines deal was found by Cheapflights users on 8/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/205:30 pmSTL - YUL
1 stop17h 27mUnited Airlines
Fri 9/268:00 pmYUL - STL
2 stops19h 27mUnited Airlines
Deal found 8/19$397
This American Airlines deal was found by Cheapflights users on 8/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/107:23 amSTL - YUL
1 stop8h 10mAmerican Airlines
Sat 9/2012:31 pmYUL - STL
1 stop10h 22mAmerican Airlines
Deal found 8/19$405
This Kiwi.com deal was found by Cheapflights users on 8/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/24:00 pmSTL - YUL
2 stops24h 55mMultiple Airlines
Thu 10/96:45 amYUL - STL
1 stop11h 25mMultiple Airlines
Deal found 8/18$416

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Montreal that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated August 20, 2025.
Use the filters below to find and compare flights from St. Louis to Montreal that are best for you.

Fly from

St. Louis

Fly to

Montreal

Route

Depart

Return

Price

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Thu 11/6

7:58 pm-3:11 pm

1 stop18h 13m

Montreal Pierre Elliott Trudeau Intl

Sun 11/9

3:52 pm-8:10 am

1 stop17h 18m

$333

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Tue 11/11

6:00 am-10:39 pm

2 stops15h 39m

Montreal Pierre Elliott Trudeau Intl

Fri 11/14

3:52 pm-8:10 am

1 stop17h 18m

$346

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 9/20

7:23 am-4:33 pm

1 stop8h 10m

Montreal Pierre Elliott Trudeau Intl

Fri 9/26

5:15 pm-9:26 am

1 stop17h 11m

$348

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 9/17

7:23 am-4:33 pm

1 stop8h 10m

Montreal Pierre Elliott Trudeau Intl

Wed 9/24

12:31 pm-9:53 pm

1 stop10h 22m

$348

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 9/27

7:23 am-4:33 pm

1 stop8h 10m

Montreal Pierre Elliott Trudeau Intl

Mon 9/29

5:15 pm-3:37 pm

1 stop23h 22m

$359

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Thu 10/16

8:05 pm-11:40 am

1 stop14h 35m

Montreal Pierre Elliott Trudeau Intl

Sat 10/25

12:30 pm-10:06 pm

1 stop10h 36m

$374

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 10/17

7:16 am-4:39 pm

1 stop8h 23m

Montreal Pierre Elliott Trudeau Intl

Sat 10/25

12:30 pm-10:06 pm

1 stop10h 36m

$378

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 10/3

6:10 am-4:33 pm

1 stop9h 23m

Montreal Pierre Elliott Trudeau Intl

Mon 10/6

12:30 pm-8:26 pm

1 stop8h 56m

$378

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 11/5

3:38 pm-3:11 pm

1 stop22h 33m

$143

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Mon 9/29

7:23 am-4:33 pm

1 stop8h 10m

$145

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/19

Showing 1-10 of 14 results
1
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Best time to book a flight from St. Louis to Montreal

Have a flexible travel schedule? Discover the best time to fly to Montreal from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Montreal

What is the cheapest month to book a flight from St. Louis to Montreal?

Currently, January is the cheapest month in which you can book a flight from St. Louis to Montreal (average of $270). Flying from St. Louis to Montreal in July is currently the most expensive (average of $409). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to YMQ?

Find hourly flight availability from St. Louis to Montreal. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 20, 2025.

A simple way to save on the total cost of your ticket is to fly from St. Louis to Montreal in the evening. If you’re flexible enough to do this you can expect to save up to 77% on your trip compared to booking a flight at noon.

Weekly flight availability from St. Louis to Montreal

Explore weekly flight availability from St. Louis to Montreal. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated August 20, 2025.

The most flights from STL to YMQ are scheduled on a Monday (2 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (2 on average).

How much does it cost to fly round-trip from St. Louis to Montreal?

Reviews of airlines servicing Montreal

Get insights into the airlines that provide service to Montreal. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Montreal. Reviews last updated August 20, 2025.
Read through reviews of airlines operating flights from St. Louis to Montreal, such as Delta, United Airlines, and American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,982 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Delta
8.0
Very good
7,982 reviews
Delta
8.0
Very good
7,982 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
United Airlines
7.4
Good
8,928 reviews
Delta
8.0
Very good
7,982 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,982 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Air Canada
7.1
Good
10,000 reviews
Delta
8.0
Very good
7,982 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Montreal. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from St. Louis to Montreal?

    Most people fly from Lambert-St Louis (STL) if they book a flight from St. Louis to Montreal. On average, Lambert-St Louis has 2 outbound flights to Montreal per day from 4 airlines. Lambert-St Louis is conveniently located just 12.7 mi from St. Louis’s city center.

  • How long is the flight from St. Louis to Montreal?

    American Airlines can get you from St. Louis to Montreal in just under 18h 13m. Your travel time can differ by up to . St. Louis and Montreal are separated by a distance of 967 mi.

  • What are the cheapest airlines flying from St. Louis to Montreal round-trip?

    Cheapflights users have booked flights from St. Louis to Montreal round-trip from $246. Other airlines that can offer you cheap pricing are Delta, from $255, and Air Canada, from $282. United Airlines is currently priced 58% below the average price you’ll pay for this route.

  • What are the most reliable airlines from St. Louis to Montreal?

    Consider Jazz (63%), United Airlines (61%) or Air Canada (58%) when booking your flight. These represent the most reliable airlines when flying from St. Louis to Montreal.

  • What are the cheapest flights from St. Louis to Montreal?

    Looking at all options, your cheapest flight can be booked for $300. While the most popular route (Lambert-St Louis - Montreal Pierre Elliott Trudeau Intl) can be booked for $397 on average our data indicates $1,933 when flying from St. Louis to Montreal.

  • Can I find deals for flights from St. Louis to Montreal that include hotel bookings?

    Yes. In addition to deals on St. Louis to Montreal flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Montreal?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Montreal.

  • Can I find deals for business class flights from St. Louis to Montreal?

    Yes. Cheapflights offers flight deals from St. Louis to Montreal by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to Montreal?

    Currently, January is the cheapest month in which you can book a flight from St. Louis to Montreal (average of $270). Flying from St. Louis to Montreal in July is currently the most expensive (average of $409). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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Top 4 airlines flying from St. Louis to Montreal

Discover the top 4 airlines that operate flights from St. Louis to Montreal. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated August 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$246Average$689FlexibilityNo cancel feeOn-time69%
DeltaCheapest$255Average$659FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$282Average$692FlexibilityNo cancel feeOn-time67%
American AirlinesCheapest$348Average$617FlexibilityNo cancel feeOn-time71%

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