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Pierre Elliott Trudeau Intl

$139+ Cheap flights from St. Louis (STL) to Pierre Elliott Trudeau Intl (YUL)

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 — YUL
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheap flight deals from St. Louis to Pierre Elliott Trudeau Intl

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Pierre Elliott Trudeau Intl (YUL). 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 11, 2025.

Round-trip from

$377
(American Airlines)

One-way from

$139
(Kiwi.com)

Popular in

February

Cheapest in

October

Average price

$738

Good round-trip deal

$674 or less

Good one-way deal

$408 or less
From Lambert-St Louis to Montreal Pierre Elliott Trudeau Intl
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One-way flight from Lambert-St Louis to Montreal Pierre Elliott Trudeau Intl
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Highest demand for flights based on searches. 22% potential increase in price ($186 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($26 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 Pierre Elliott Trudeau Intl.
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Price to beat on a one-way flight from Lambert-St Louis to Montreal Pierre Elliott Trudeau Intl.
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Find flight deals from St. Louis to Pierre Elliott Trudeau Intl

Cheapest flights from St. Louis to Pierre Elliott Trudeau Intl
Explore the most affordable flight options available from St. Louis to Pierre Elliott Trudeau Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This American Airlines deal was found by Cheapflights users on 9/10. 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 10/254:34 pmSTL - YUL
1 stop18h 06mAmerican Airlines
Sat 11/112:30 pmYUL - STL
1 stop10h 38mAmerican Airlines
Deal found 9/10$377
This Kiwi.com deal was found by Cheapflights users on 9/9. 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 11/109:07 pmSTL - YUL
2 stops26h 36mMultiple Airlines
Sun 11/164:35 pmYUL - STL
1 stop18h 05mMultiple Airlines
Deal found 9/9$401
This Kiwi.com deal was found by Cheapflights users on 9/10. 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
2 stops11h 25mMultiple Airlines
Mon 12/84:35 pmYUL - STL
1 stop31h 11mMultiple Airlines
Deal found 9/10$409
This American Airlines deal was found by Cheapflights users on 9/10. 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 10/45:25 pmSTL - YUL
1 stop17h 21mAmerican Airlines
Tue 10/712:30 pmYUL - STL
1 stop8h 56mAmerican Airlines
Deal found 9/10$411
This American Airlines deal was found by Cheapflights users on 9/10. 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 12/68:41 amSTL - YUL
2 stops13h 01mAmerican Airlines
Tue 12/97:30 amYUL - STL
2 stops13h 54mAmerican Airlines
Deal found 9/10$426
This American Airlines deal was found by Cheapflights users on 9/10. 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 10/178:05 pmSTL - YUL
1 stop14h 35mAmerican Airlines
Mon 10/205:24 pmYUL - STL
1 stop15h 45mAmerican Airlines
Deal found 9/10$428
This Kiwi.com deal was found by Cheapflights users on 9/8. 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 10/39:32 pmSTL - YUL
1 stop15h 48mMultiple Airlines
Sat 10/117:20 pmYUL - STL
2 stops16h 17mMultiple Airlines
Deal found 9/8$429
This Kiwi.com deal was found by Cheapflights users on 9/11. 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 9/11$436
This American Airlines deal was found by Cheapflights users on 9/10. 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.
Mon 10/276:00 amSTL - YUL
1 stop9h 39mAmerican Airlines
Wed 10/297:50 amYUL - STL
2 stops11h 30mAmerican Airlines
Deal found 9/10$437

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Pierre Elliott Trudeau Intl 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 11, 2025.
Use the filters below to find and compare flights from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport that are best for you.

Fly from

St. Louis

Fly to

Pierre Elliott Trudeau Intl

Route

Depart

Return

Price

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 10/25

4:34 pm-11:40 am

1 stop18h 06m

Montreal Pierre Elliott Trudeau Intl

Sat 11/1

12:30 pm-10:08 pm

1 stop10h 38m

$377

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 12/5

9:45 am-10:10 pm

2 stops11h 25m

Montreal Pierre Elliott Trudeau Intl

Mon 12/8

4:35 pm-10:46 pm

1 stop31h 11m

$409

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 10/17

8:05 pm-11:40 am

1 stop14h 35m

Montreal Pierre Elliott Trudeau Intl

Mon 10/20

5:24 pm-8:09 am

1 stop15h 45m

$428

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 10/3

9:32 pm-2:20 pm

1 stop15h 48m

Montreal Pierre Elliott Trudeau Intl

Sat 10/11

7:20 pm-10:37 am

2 stops16h 17m

$429

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-8:09 am

1 stop17h 17m

$444

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 10/4

7:10 am-7:25 pm

2 stops11h 15m

Montreal Pierre Elliott Trudeau Intl

Tue 10/7

9:28 am-8:23 pm

2 stops11h 55m

$469

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Mon 11/10

2:12 pm-12:30 am

1 stop9h 18m

Montreal Pierre Elliott Trudeau Intl

Sun 11/16

4:35 pm-9:40 am

1 stop18h 05m

$475

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Sat 10/25

7:15 pm-10:45 pm

3 stops26h 30m

Montreal Pierre Elliott Trudeau Intl

Sat 11/1

10:15 am-11:02 am

3 stops25h 47m

$487

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Tue 2/17

6:00 am-6:49 pm

1 stop11h 49m

Montreal Pierre Elliott Trudeau Intl

Thu 2/19

7:45 pm-3:52 pm

1 stop21h 07m

$541

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 10/1

3:23 pm-10:40 am

1 stop18h 17m

Montreal Pierre Elliott Trudeau Intl

Sun 10/12

6:15 am-3:44 pm

1 stop10h 29m

$542

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

Showing 1-10 of 17 results
1
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Best time to book a flight from St. Louis to Pierre Elliott Trudeau Intl

Have a flexible travel schedule? Discover the best time to fly to Pierre Elliott Trudeau Intl 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 Pierre Elliott Trudeau Intl Airport

What is the cheapest month to book a flight from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport?

Currently, January is the cheapest month in which you can book a flight from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport (average of $270). Flying from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport 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 YUL?

Find hourly flight availability from St. Louis to Pierre Elliott Trudeau Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 11, 2025.

It’s typically best to fly out from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport in the evening. Doing so could potentially save you 75% on the flight price compared to flying at noon, which is usually more expensive.

Reviews of airlines servicing Pierre Elliott Trudeau Intl

Get insights into the airlines that provide service to Pierre Elliott Trudeau Intl. 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 Pierre Elliott Trudeau Intl. Reviews last updated September 11, 2025.
Get a feel of what it's like to fly with Delta, United Airlines, and American Airlines from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,960 reviews

Food

7.3

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
7,960 reviews
Delta
8.0
Very good
7,960 reviews

Food

7.3

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
8,937 reviews
Delta
8.0
Very good
7,960 reviews

Food

7.3

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
7,960 reviews

Food

7.3

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
7,960 reviews

Food

7.3

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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 Pierre Elliott Trudeau Intl. 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 Pierre Elliott Trudeau Intl?

    Most people fly from Lambert-St Louis (STL) if they book a flight from St. Louis to Montreal Pierre Elliott Trudeau Intl. On average, Lambert-St Louis has 2 outbound flights to Montreal Pierre Elliott Trudeau Intl 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 Pierre Elliott Trudeau Intl Airport?

    There are many flights that can get you from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport in 18h 06m. Fly via American Airlines to get the fastest option. There are 967 mi between St. Louis and Montreal Pierre Elliott Trudeau Intl Airport.

  • What are the cheapest airlines flying from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport round-trip?

    Currently priced at $246, United Airlines will fly you from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport and back. In addition to United Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Delta and Air Canada - these airlines can fly you to your destination from $255 and $282, respectively. United Airlines is 62% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the most reliable airlines from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport?

    Before booking your flight to Montreal Pierre Elliott Trudeau Intl Airport from St. Louis, check out the most reliable airlines to get you to your destination on time: Air Canada (74%), Jazz (74%), United Airlines( 74%).

  • What are the cheapest flights from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport?

    The cheapest flight price from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport is $297. On average you can expect to pay $2,138. The most popular route, (Lambert-St Louis - Montreal Pierre Elliott Trudeau Intl), can usually be booked for $401.

  • Can I find deals for flights from St. Louis to Pierre Elliott Trudeau Intl that include hotel bookings?

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

  • How can I find direct flights from St. Louis to Pierre Elliott Trudeau Intl?

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

  • Can I find deals for business class flights from St. Louis to Pierre Elliott Trudeau Intl?

    Yes. Cheapflights offers flight deals from St. Louis to Pierre Elliott Trudeau Intl 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 Pierre Elliott Trudeau Intl Airport?

    Currently, January is the cheapest month in which you can book a flight from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport (average of $270). Flying from St. Louis to Montreal Pierre Elliott Trudeau Intl Airport 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

Traveling to a place near Montreal Pierre Elliott Trudeau Intl Airport?

Book flights to Montreal Pierre Elliott Trudeau Intl Airport if you plan to visit one of these locations
Laval
Longueuil
Brossard
Sherbrooke
Dorval

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Alternative routes for St. Louis to Pierre Elliott Trudeau Intl

See prices for flight routes from nearby airports that may be better suited for you.
Kansas City to Pierre Elliott Trudeau Intl flights
Springfield to Pierre Elliott Trudeau Intl flights
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Joplin to Pierre Elliott Trudeau Intl flights

Top 4 airlines flying from St. Louis to Pierre Elliott Trudeau Intl

Discover the top 4 airlines that operate flights from St. Louis to Pierre Elliott Trudeau Intl. 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 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$246Average$703FlexibilityNo cancel feeOn-time69%
DeltaCheapest$255Average$595FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$282Average$694FlexibilityNo cancel feeOn-time67%
American AirlinesCheapest$348Average$578FlexibilityNo cancel feeOn-time71%

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