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$148+ 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 10/30. Fares are subject to change and may not be available on all flights or dates of travel.
STL — YMQ
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
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 September 17, 2025.

Round-trip from

$367
(Kiwi.com)

One-way from

$148
(Kiwi.com)

Popular in

February

Cheapest in

June

Average price

$692

Good round-trip deal

$704 or less

Good one-way deal

$408 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. 13% potential increase in price ($97 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($14 potential savings vs. average RT price).
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Average for round-trip flights in September 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 September 17, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/16. 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 12/412:20 pmSTL - YUL
1 stop27h 08mMultiple Airlines
Sun 12/74:35 pmYUL - STL
1 stop17h 10mMultiple Airlines
Deal found 9/16$367
This Kiwi.com deal was found by Cheapflights users on 9/15. 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 10/3010:57 amSTL - YUL
1 stop27h 13mMultiple Airlines
Thu 11/62:30 pmYUL - STL
2 stops24h 27mMultiple Airlines
Deal found 9/15$376
This Kiwi.com deal was found by Cheapflights users on 9/14. 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.
Fri 12/59:45 amSTL - YUL
1 stop13h 45mMultiple Airlines
Sat 12/65:25 pmYUL - STL
2 stops18h 36mMultiple Airlines
Deal found 9/14$404
This American Airlines deal was found by Cheapflights users on 9/15. 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 10/307:16 amSTL - YUL
1 stop8h 23mAmerican Airlines
Thu 11/63:52 pmYUL - STL
1 stop9h 04mAmerican Airlines
Deal found 9/15$408
This American Airlines deal was found by Cheapflights users on 9/15. 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 10/214:34 pmSTL - YUL
1 stop18h 06mAmerican Airlines
Wed 11/127:30 amYUL - STL
2 stops13h 53mAmerican Airlines
Deal found 9/15$418
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Sun 10/2610:57 amSTL - YUL
1 stop27h 13mMultiple Airlines
Fri 10/312:30 pmYUL - STL
2 stops26h 26mMultiple Airlines
Deal found 9/15$423
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Sun 10/2610:57 amSTL - YUL
2 stops28h 58mMultiple Airlines
Sun 11/24:35 pmYUL - STL
1 stop18h 05mMultiple Airlines
Deal found 9/15$432
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Mon 10/279:59 pmSTL - YUL
2 stops40h 13mMultiple Airlines
Sun 11/24:35 pmYUL - STL
1 stop18h 05mMultiple Airlines
Deal found 9/15$448
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Sun 10/2610:57 amSTL - YUL
1 stop27h 13mMultiple Airlines
Sat 11/15:10 pmYUL - STL
2 stops42h 30mMultiple Airlines
Deal found 9/15$451
This American Airlines deal was found by Cheapflights users on 9/16. 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 10/177:16 amSTL - YUL
1 stop8h 23mAmerican Airlines
Mon 10/205:24 pmYUL - STL
1 stop15h 45mAmerican Airlines
Deal found 9/16$455
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Fri 12/59:45 amSTL - YUL
1 stop13h 45mMultiple Airlines
Mon 12/86:45 amYUL - STL
2 stops17h 01mMultiple Airlines
Deal found 9/15$462

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 September 17, 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 10/30

7:16 am-4:39 pm

1 stop8h 23m

Montreal Pierre Elliott Trudeau Intl

Thu 11/6

3:52 pm-11:56 pm

1 stop9h 04m

$408

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 10/24

7:16 am-4:39 pm

1 stop8h 23m

Montreal Pierre Elliott Trudeau Intl

Mon 10/27

5:24 pm-9:28 am

1 stop17h 04m

$455

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

Mon 10/20

5:24 pm-8:09 am

1 stop15h 45m

$455

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 12/3

5:40 pm-3:10 pm

1 stop20h 30m

Montreal Pierre Elliott Trudeau Intl

Sun 12/7

3:52 pm-8:11 am

1 stop17h 19m

$464

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 10/24

6:42 pm-2:20 pm

1 stop18h 38m

Montreal Pierre Elliott Trudeau Intl

Mon 10/27

6:45 am-7:26 pm

2 stops13h 41m

$471

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 12/5

9:45 am-12:30 am

1 stop13h 45m

Montreal Pierre Elliott Trudeau Intl

Sat 12/6

4:35 pm-8:45 am

1 stop17h 10m

$515

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Tue 11/4

11:05 am-10:20 am

1 stop22h 15m

Montreal Pierre Elliott Trudeau Intl

Tue 11/18

6:00 am-3:47 pm

1 stop10h 47m

$522

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Thu 10/16

5:00 am-1:54 pm

1 stop7h 54m

Montreal Pierre Elliott Trudeau Intl

Sat 10/18

8:20 am-10:35 pm

1 stop15h 15m

$522

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Tue 10/21

6:30 am-9:29 pm

1 stop13h 59m

Montreal Pierre Elliott Trudeau Intl

Wed 11/12

6:00 am-3:49 pm

1 stop10h 49m

$522

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sun 11/2

10:57 am-12:43 am

2 stops36h 46m

$155

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 17 results
1
2

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 September 17, 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 September 17, 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 September 17, 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
7,961 reviews

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Entertainment

7.9

Overall

8.0

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
7,961 reviews
Delta
8.0
Very good
7,961 reviews

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Entertainment

7.9

Overall

8.0

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
8,926 reviews
Delta
8.0
Very good
7,961 reviews

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Entertainment

7.9

Overall

8.0

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
7,961 reviews

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Entertainment

7.9

Overall

8.0

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
7,961 reviews

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Entertainment

7.9

Overall

8.0

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 8h 23m. 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 59% below the average price you’ll pay for this route.

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

    Consider Sun Country Air (100%), Air Canada (82%) or Jazz (82%) 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 $297. While the most popular route (Lambert-St Louis - Montreal Pierre Elliott Trudeau Intl) can be booked for $367 on average, our data indicates $2,177 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 September 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$246Average$765FlexibilityNo cancel feeOn-time69%
DeltaCheapest$255Average$595FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$282Average$692FlexibilityNo cancel feeOn-time67%
American AirlinesCheapest$348Average$617FlexibilityNo cancel feeOn-time71%

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