HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
St. Louis

$243+ 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 8/24. Fares are subject to change and may not be available on all flights or dates of travel.
YUL — STL
Jul 15 — Jul 221
Wed 7/15
Wed 7/22
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Pierre Elliott Trudeau Intl to St. Louis with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 June 15, 2026.

This American Airlines deal was found by Cheapflights users on 6/12. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/2312:31 pm
YUL
-
STL
1 stop12h 56m
American Airlines
Fri 9/254:37 pm
STL
-
YUL
1 stop16h 12m
American Airlines
Deal found 6/12$435
This American Airlines deal was found by Cheapflights users on 6/11. 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.
Tue 8/185:34 pm
YUL
-
STL
1 stop15h 49m
American Airlines
Sat 11/76:00 am
STL
-
YUL
1 stop8h 11m
American Airlines
Deal found 6/11$462
This United Airlines deal was found by Cheapflights users on 6/14. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/216:30 pm
YUL
-
STL
1 stop15h 19m
United Airlines
Tue 7/289:20 am
STL
-
YUL
1 stop8h 43m
United Airlines
Deal found 6/14$480
This Air Canada deal was found by Cheapflights users on 6/14. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/154:55 pm
YUL
-
STL
Nonstop2h 46m
Air Canada
Mon 10/1912:10 pm
STL
-
YUL
Nonstop2h 31m
Air Canada
Deal found 6/14$485
This Delta deal was found by Cheapflights users on 6/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/49:28 am
YUL
-
STL
1 stop12h 23m
Delta
Sat 11/76:00 am
STL
-
YUL
1 stop6h 36m
Delta
Deal found 6/11$489
This Air Canada deal was found by Cheapflights users on 6/15. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/110:10 am
YUL
-
STL
1 stop4h 50m
Air Canada
Sun 10/412:10 pm
STL
-
YUL
Nonstop2h 31m
Air Canada
Deal found 6/15$490
This United Airlines deal was found by Cheapflights users on 6/11. 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 11/43:00 pm
YUL
-
STL
1 stop5h 40m
United Airlines
Sat 11/76:40 am
STL
-
YUL
2 stops7h 22m
United Airlines
Deal found 6/11$491
This Delta deal was found by Cheapflights users on 6/10. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/156:00 am
YUL
-
STL
1 stop8h 20m
Delta
Mon 10/193:42 pm
STL
-
YUL
1 stop7h 09m
Delta
Deal found 6/10$492
This Delta deal was found by Cheapflights users on 6/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/35:10 pm
YUL
-
STL
1 stop4h 25m
Delta
Sat 10/105:30 pm
STL
-
YUL
1 stop5h 21m
Delta
Deal found 6/11$493

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 June 15, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$435
(American Airlines)

One-way from

$243
(Kiwi.com)

Popular in

December

Cheapest in

November

Average price

$740

Good one-way deal

$326 or less
Provider with most accurate pricing for Montreal Pierre Elliott Trudeau Intl-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Montreal Pierre Elliott Trudeau Intl-Lambert-St Louis flights.
Search Deals
From Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis
Search Deals
One-way flight from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($72 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($15 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals
Price to beat on a one-way flight from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis.
Search Deals

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 June 15, 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

Tue 7/21

8:30 am-9:26 pm

2 stops13h 56m

Lambert-St Louis

Tue 7/28

7:05 pm-7:03 pm

1 stop22h 58m

$480

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 10/15

7:00 am-12:56 pm

1 stop6h 56m

Lambert-St Louis

Mon 10/19

7:20 am-5:03 pm

1 stop8h 43m

$491

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 11/4

3:00 pm-7:40 pm

1 stop5h 40m

Lambert-St Louis

Sat 11/7

6:40 am-3:02 pm

2 stops7h 22m

$491

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 11/4

7:00 am-12:56 pm

1 stop6h 56m

Lambert-St Louis

Sat 11/7

6:00 am-1:36 pm

1 stop6h 36m

$491

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 9/23

6:00 am-2:15 pm

2 stops9h 15m

Lambert-St Louis

Fri 9/25

5:36 pm-2:40 pm

2 stops20h 04m

$491

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sat 10/3

9:15 am-6:16 pm

2 stops10h 01m

Lambert-St Louis

Sat 10/10

11:35 am-5:30 pm

1 stop4h 55m

$493
Quickest round-trip

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 10/15

10:10 am-2:00 pm

1 stop4h 50m

Lambert-St Louis

Mon 10/19

12:10 pm-3:41 pm

Nonstop2h 31m

$494
Cheapest one-way

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 7/8

12:50 pm-5:37 pm

3 stops29h 47m

$252

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 7/7

6:30 pm-3:46 pm

1 stop22h 16m

$270

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 7/8

8:40 am-9:26 pm

1 stop13h 46m

$270

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/13

Showing 1-10 of 17 resultsSorted by cheapest first
1
2
  • 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, November is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of $542). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in December is currently the most expensive (average of $778). 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 YUL to STL?

Find hourly flight availability from Pierre Elliott Trudeau Intl to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 15, 2026.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis as you normally would.

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.

Read more
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.

Read 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 June 15, 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.
Air Canada
7.1
Good
11,194 reviews

Entertainment

6.8

Crew

7.8

Food

6.3

Boarding

7.3

Overall

7.1

Comfort

7.1

Reviews

1 / 20
2.0
Mediocre

Anonymous,Jun 2026

YUL - LYS

The flight was cancelled. We were rebooked the next day on Air France but had a 12 hour layover in Paris. We lost 1 1/2 days of our vacation.
Air Canada
7.1
Good
11,194 reviews
Air Canada
7.1
Good
11,194 reviews

Entertainment

6.8

Crew

7.8

Food

6.3

Boarding

7.3

Overall

7.1

Comfort

7.1

Reviews

1 / 20
2.0
Mediocre

Anonymous,Jun 2026

YUL - LYS

The flight was cancelled. We were rebooked the next day on Air France but had a 12 hour layover in Paris. We lost 1 1/2 days of our vacation.

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 2 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 and Delta can get you from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in just under 6h 56m. Your travel time can differ by up to 7h. 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.

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

    While on average a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis is generally $386, our data shows the cheapest flight currently is $254. When looking at the most popular route, (Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis), you can expect to pay $480 for that flight.

  • 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, November is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of $542). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in December is currently the most expensive (average of $778). 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
Eureka
Maryland Heights
Collinsville
Wentzville
Glencoe
Chesterfield
Alton
Farmington

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

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 June 15, 2026.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$470Average$584FlexibilityNo cancel feeOn-time67%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.