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$189+ 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 9/19. Fares are subject to change and may not be available on all flights or dates of travel.
YUL — STL
Aug 3 — Aug 101
Sun 8/3
Sun 8/10
1 adult, Economy
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Cheap 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 July 29, 2025.

Round-trip from

$316
(American Airlines)

One-way from

$189
(American Airlines)

Popular in

December

Cheapest in

May

Average price

$669

Good one-way deal

$279 or less
From Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis
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One-way flight from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis
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Highest demand for flights based on searches. 2% potential increase in price ($13 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 July 2025
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Price to beat on a one-way flight from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis.
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Find 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 July 29, 2025.

This American Airlines deal was found by Cheapflights users on 7/27. 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 9/1012:31 pmYUL - STL
1 stop9h 01mAmerican Airlines
Wed 9/177:23 amSTL - YUL
1 stop8h 10mAmerican Airlines
Deal found 7/27$316
This Booking.com deal was found by Cheapflights users on 7/27. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/286:10 pmYUL - STL
Nonstop2h 50mAir Canada
Mon 9/11:30 pmSTL - YUL
Nonstop2h 30mAir Canada
Deal found 7/27$456
This Mytrip deal was found by Cheapflights users on 7/27. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/288:30 pmYUL - STL
2 stops18h 02mMultiple Airlines
Mon 9/12:30 pmSTL - YUL
3 stops21h 50mMultiple Airlines
Deal found 7/27$467
This Delta deal was found by Cheapflights users on 7/28. 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 9/106:00 amYUL - STL
2 stops11h 06mDelta
Wed 9/176:05 amSTL - YUL
1 stop9h 00mDelta
Deal found 7/28$472
This United Airlines deal was found by Cheapflights users on 7/29. 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.
Fri 9/127:10 pmYUL - STL
2 stops16h 30mUnited Airlines
Fri 9/197:04 pmSTL - YUL
1 stop17h 50mUnited Airlines
Deal found 7/29$476

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 July 29, 2025.
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

Pierre Elliott Trudeau Intl

Fly to

St. Louis

Route

Depart

Return

Price

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 9/10

12:31 pm-8:32 pm

1 stop9h 01m

Lambert-St Louis

Wed 9/17

7:23 am-4:33 pm

1 stop8h 10m

$316

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 8/28

6:10 pm-8:00 pm

Nonstop2h 50m

Lambert-St Louis

Mon 9/1

1:30 pm-5:00 pm

Nonstop2h 30m

$456

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 9/10

6:00 am-4:06 pm

2 stops11h 06m

Lambert-St Louis

Wed 9/17

6:05 am-4:05 pm

1 stop9h 00m

$472

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 9/12

7:10 pm-10:40 am

2 stops16h 30m

Lambert-St Louis

Fri 9/19

7:04 pm-1:54 pm

1 stop17h 50m

$476

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 9/12

7:00 am-4:35 pm

3 stops10h 35m

Lambert-St Louis

Fri 9/19

1:00 pm-3:20 pm

3 stops25h 20m

$481

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 9/19

5:15 pm-9:26 am

1 stop17h 11m

$189

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 9/11

6:45 am-1:02 pm

2 stops31h 17m

$227

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 8/19

6:15 am-2:33 pm

1 stop9h 18m

$257

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 9/19

6:10 pm-7:57 pm

Nonstop2h 47m

$264

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 9/14

7:00 am-12:31 pm

1 stop6h 31m

$273

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/27

Showing 1-10 of 11 results
1
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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, August is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of $311). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in March is currently the most expensive (average of $356). 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 July 29, 2025.

It’s typically best to fly out from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in the evening. Doing so could potentially save you 53% on the flight price compared to flying at noon, which is usually more expensive.

Weekly flight availability from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis

Explore weekly flight availability from Pierre Elliott Trudeau Intl to St. Louis. 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 July 29, 2025.

The most flights from YUL to STL 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).

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 July 29, 2025.
Peruse reviews from past customers who have flown with Delta, United Airlines, and American Airlines 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.
Delta
8.0
Very good
7,979 reviews

Food

7.3

Overall

8.0

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
Delta
8.0
Very good
7,979 reviews
Delta
8.0
Very good
7,979 reviews

Food

7.3

Overall

8.0

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
United Airlines
7.4
Good
8,896 reviews
Delta
8.0
Very good
7,979 reviews

Food

7.3

Overall

8.0

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,979 reviews

Food

7.3

Overall

8.0

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
WestJet
7.2
Good
2,972 reviews
Delta
8.0
Very good
7,979 reviews

Food

7.3

Overall

8.0

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
Air Canada
7.1
Good
9,826 reviews
Delta
8.0
Very good
7,979 reviews

Food

7.3

Overall

8.0

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.

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. 2 airlines have flights to Lambert-St Louis from Montreal Pierre Elliott Trudeau Intl on a regular basis.

  • What are the cheapest airlines flying 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 American Airlines. Our recent data shows that you can find tickets from as low as $316 on this airline. Additional options worth looking into are Air Canada and Delta, starting at $456 and $472 round-trip. American Airlines is priced at 45% lower than the current average price of a flight leaving 3 months from now.

  • What are the cheapest airlines to fly from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis one-way?

    $189 is the cheapest one-way deal found within the past few days, from American Airlines. You may also be able to find cheap deals on United Airlines and Air Canada, with prices starting from $257 and $264, respectively.

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

    No one likes to see their flight delayed. When booking a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis consider choosing Jazz (67%), Air Canada (63%) or United Airlines (62%) as they are the most reliable in getting you off to your destination on time.

  • 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 $332, our data shows the cheapest flight currently is $241. When looking at the most popular route, (Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis), you can expect to pay $384 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, August is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of $311). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in March is currently the most expensive (average of $356). 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
O'Fallon
Maryland Heights
Fairview Heights
Collinsville
Eureka
St. Peters
Glencoe
Alton
Chesterfield
Festus
Farmington

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Alternative routes for Pierre Elliott Trudeau Intl to St. Louis

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Top 2 airlines flying from Pierre Elliott Trudeau Intl to St. Louis

Discover the top 2 airlines 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 July 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$433Average$542FlexibilityNo cancel feeOn-time67%
DeltaCheapest$452Average$511FlexibilityNo cancel feeOn-timeN/A

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