St. Louis

$216+ Cheap flights from Pierre Elliott Trudeau Intl (YUL) to St. Louis (STL)

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 4/26. Fares are subject to change and may not be available on all flights or dates of travel.
YUL — STL
Apr 15 — Apr 221
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Cheap flight deals from Pierre Elliott Trudeau Intl to St. Louis

Cheapest flights from Pierre Elliott Trudeau Intl to St. Louis
Explore the most affordable flight options available from Pierre Elliott Trudeau Intl to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 16, 2026.

This American Airlines deal was found by Cheapflights users on 3/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/2012:30 pm
YUL
-
STL
1 stop12h 16m
American Airlines
Sat 4/252:33 pm
STL
-
YUL
1 stop20h 11m
American Airlines
Deal found 3/11$391
This American Airlines deal was found by Cheapflights users on 3/14. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/2812:30 pm
YUL
-
STL
1 stop12h 16m
American Airlines
Tue 5/54:30 pm
STL
-
YUL
1 stop18h 14m
American Airlines
Deal found 3/14$394
This American Airlines deal was found by Cheapflights users on 3/15. 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 5/512:30 pm
YUL
-
STL
1 stop10h 49m
American Airlines
Sat 5/98:03 pm
STL
-
YUL
1 stop14h 41m
American Airlines
Deal found 3/15$398
This American Airlines deal was found by Cheapflights users on 3/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/2512:30 pm
YUL
-
STL
1 stop8h 39m
American Airlines
Sat 5/28:03 pm
STL
-
YUL
1 stop14h 41m
American Airlines
Deal found 3/11$412
This United Airlines deal was found by Cheapflights users on 3/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/151:20 pm
YUL
-
STL
1 stop8h 53m
United Airlines
Sat 4/188:21 am
STL
-
YUL
1 stop8h 09m
United Airlines
Deal found 3/11$435
This American Airlines deal was found by Cheapflights users on 3/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/2312:30 pm
YUL
-
STL
1 stop12h 24m
American Airlines
Sat 5/309:08 am
STL
-
YUL
1 stop6h 45m
American Airlines
Deal found 3/11$464
This SmartFares deal was found by Cheapflights users on 3/14. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/26:30 pm
YUL
-
STL
Nonstop2h 55m
Air Canada
Sun 5/31:00 pm
STL
-
YUL
Nonstop2h 35m
Air Canada
Deal found 3/14$486
This United Airlines deal was found by Cheapflights users on 3/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/288:30 am
YUL
-
STL
2 stops13h 46m
United Airlines
Mon 6/18:15 pm
STL
-
YUL
2 stops14h 11m
United Airlines
Deal found 3/11$491
This SmartFares deal was found by Cheapflights users on 3/12. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/2610:10 am
YUL
-
STL
1 stop6h 15m
Air Canada
Sun 5/31:00 pm
STL
-
YUL
Nonstop2h 35m
Air Canada
Deal found 3/12$499
This American Airlines deal was found by Cheapflights users on 3/14. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/1612:30 pm
YUL
-
STL
1 stop12h 16m
American Airlines
Wed 4/298:03 pm
STL
-
YUL
1 stop14h 41m
American Airlines
Deal found 3/14$500

Find flight deals from Pierre Elliott Trudeau Intl to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Pierre Elliott Trudeau Intl (YUL) to St. Louis (STL). 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 March 16, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$391
(American Airlines)

One-way from

$216
(Kiwi.com)

Popular in

December

Cheapest in

April

Average price

$551
Provider with most accurate pricing for Montreal Pierre Elliott Trudeau Intl-Lambert-St Louis flight deals.
Provider most trusted by Cheapflights users for Montreal Pierre Elliott Trudeau Intl-Lambert-St Louis flights.
From Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis
One-way flight from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis
Highest demand for flights based on searches. 10% potential increase in price ($74 potential increase over avg. RT price).
Cheapest flight prices on average. 2% potential price decrease ($16 potential savings vs. average RT price).
Average for round-trip flights in March 2026

Cheapflights Fare Finder

 
Customize your flight search to find flights from Pierre Elliott Trudeau Intl to St. Louis 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 March 16, 2026.
Use the filters below to find and compare flights from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 4/15

1:20 pm-9:13 pm

1 stop8h 53m

Lambert-St Louis

Sat 4/18

8:21 am-5:30 pm

1 stop8h 09m

$435

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 5/28

8:30 am-9:16 pm

2 stops13h 46m

Lambert-St Louis

Mon 6/1

8:15 pm-11:26 am

2 stops14h 11m

$491

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 4/26

10:10 am-3:25 pm

1 stop6h 15m

Lambert-St Louis

Sun 5/3

1:00 pm-4:35 pm

Nonstop2h 35m

$499

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 5/21

6:00 am-9:29 am

1 stop4h 29m

Lambert-St Louis

Tue 5/26

6:04 pm-8:39 am

2 stops13h 35m

$521

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 5/10

6:10 am-10:48 am

1 stop5h 38m

Lambert-St Louis

Sat 5/16

7:45 am-9:26 pm

1 stop12h 41m

$521

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 5/10

6:00 am-9:29 am

1 stop4h 29m

Lambert-St Louis

Sat 5/16

5:36 pm-11:41 pm

1 stop5h 05m

$522

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 5/21

6:00 am-3:46 pm

2 stops10h 46m

Lambert-St Louis

Tue 5/26

6:00 am-4:10 pm

2 stops9h 10m

$522
Quickest round-trip

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 5/10

6:30 pm-8:25 pm

Nonstop2h 55m

Lambert-St Louis

Sat 5/16

7:05 am-1:21 pm

1 stop5h 16m

$525

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 8/10

8:00 pm-6:02 pm

2 stops23h 02m

Lambert-St Louis

Sun 8/16

6:00 am-11:56 pm

1 stop16h 56m

$531

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 4/15

9:30 am-4:24 pm

1 stop7h 54m

Lambert-St Louis

Sat 4/18

3:25 pm-11:26 pm

1 stop7h 01m

$532

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/11

Showing 1-10 of 22 resultsSorted by cheapest first
1
2
3
  • Most accurate provider: When it comes to deals on Montreal Pierre Elliott Trudeau Intl Airport-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Montreal Pierre Elliott Trudeau Intl Airport-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Montreal Pierre Elliott Trudeau Intl Airport-St. Louis flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Montreal Pierre Elliott Trudeau Intl Airport-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Montreal Pierre Elliott Trudeau Intl Airport-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Pierre Elliott Trudeau Intl to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Pierre Elliott Trudeau Intl 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 Montreal Pierre Elliott Trudeau Intl Airport to St. Louis

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

Currently, September is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of $336). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in January is currently the most expensive (average of $640). 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.

How much does it cost to fly round-trip from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis?

The best insider tips for Montreal Pierre Elliott Trudeau Intl Airport to St. Louis flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Montreal Pierre Elliott Trudeau Intl Airport to St. Louis trip
Our travel experts
John Walton

John Walton

Expert on YUL

Independent aviation journalist John Walton took his first flight at eight weeks old and hasn’t stopped travelling since. A world-renowned expert in airlines and the passenger experience, he writes in depth on aviation, is a resident expert on travel in Japan and France, and offers a uniquely queer perspective on travelling the world.

Taryn White

Taryn White

Expert on STL

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated March 16, 2026.
Peruse reviews from past customers who have flown with Air Canada from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Overall

7.1

Food

6.3

Entertainment

6.8

Crew

7.8

Boarding

7.3

Comfort

7.1

Reviews

1 / 20
6.0
Good

Paula,Mar 2026

YVR - PSP

Everything was OK, but we waited on the tarmac for an hour and 20 minutes after landing because there was no available gate. This is a daily occurrence at the Palm Springs airport, and happens with Air Canada and WestJet constantly.

Overall

7.1

Food

6.3

Entertainment

6.8

Crew

7.8

Boarding

7.3

Comfort

7.1

Reviews

1 / 20
6.0
Good

Paula,Mar 2026

YVR - PSP

Everything was OK, but we waited on the tarmac for an hour and 20 minutes after landing because there was no available gate. This is a daily occurrence at the Palm Springs airport, and happens with Air Canada and WestJet constantly.

Related info for your journey

Find useful and relevant information for your journey from Pierre Elliott Trudeau Intl to St. Louis. 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 into for flights to St. Louis from Montreal Pierre Elliott Trudeau Intl?

    For a flight from Montreal Pierre Elliott Trudeau Intl to St. Louis, you will be flying into Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city. Lambert-St Louis is the only St. Louis airport and it handles 0 inbound flights from Montreal Pierre Elliott Trudeau Intl per day. 1 airline has flights to Lambert-St Louis from Montreal Pierre Elliott Trudeau Intl on a regular basis.

  • How long is the flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis?

    United Airlines, Air Canada, and Delta can get you from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in just under 4h 29m. Your travel time can differ by up to 4h 24m. The distance from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis is about 967 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What is the cheapest airline to fly from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis round-trip?

    Our cheapest airline available from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis is Air Canada. Our recent data shows that you can find tickets from as low as $470 on this airline. Air Canada is priced at 24% lower than the current average price of a flight leaving 3 months from now.

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

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

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

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

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

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

    Currently, September is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of $336). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in January is currently the most expensive (average of $640). 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 St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fenton
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Wentzville
Glencoe
Chesterfield
Alton
Farmington
Festus

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Top airline flying from Pierre Elliott Trudeau Intl to St. Louis

Discover the top airline that operate flights from Pierre Elliott Trudeau Intl to St. Louis. 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 March 16, 2026.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$470Average$589FlexibilityNo cancel feeOn-time67%

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