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Cheap flights from Montreal to St. Louis from C$ 261

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 30/3. Fares are subject to change and may not be available on all flights or dates of travel.
YMQ — STL
2 Apr — 9 Apr1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Montreal to St. Louis

Enter your travel dates to find the best prices.

Cheapest flights from Montreal to St. Louis
Explore the most affordable flight options available from Montreal to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 3 March 2026.

Mon 20/412:30 p.m.
YUL
-
STL
1 stop12h 16m
American Airlines
Sat 25/45:21 p.m.
STL
-
YUL
1 stop17h 23m
American Airlines
Deal found 27/2C$ 477
Thu 14/512:30 p.m.
YUL
-
STL
1 stop12h 26m
American Airlines
Tue 19/55:51 a.m.
STL
-
YUL
1 stop4h 53m
American Airlines
Deal found 27/2C$ 556
Sun 12/44:35 p.m.
YUL
-
STL
1 stop16h 16m
Multiple Airlines
Sun 19/49:55 p.m.
STL
-
YUL
2 stops34h 25m
Multiple Airlines
Deal found 26/2C$ 564
Tue 8/94:55 p.m.
YUL
-
STL
Nonstop2h 46m
Air Canada
Wed 9/912:10 p.m.
STL
-
YUL
Nonstop2h 31m
Air Canada
Deal found 1/3C$ 581
Mon 18/56:30 p.m.
YUL
-
STL
Nonstop2h 55m
Air Canada
Sun 24/57:05 a.m.
STL
-
YUL
2 stops7h 19m
Air Canada
Deal found 26/2C$ 582
Mon 30/34:55 p.m.
YUL
-
STL
1 stop5h 13m
United Airlines
Tue 31/36:15 a.m.
STL
-
YUL
1 stop5h 54m
United Airlines
Deal found 27/2C$ 601
Fri 1/56:30 p.m.
YUL
-
STL
Nonstop2h 55m
Air Canada
Fri 8/51:00 p.m.
STL
-
YUL
Nonstop2h 35m
Air Canada
Deal found 2/3C$ 605

Find flight deals from Montreal to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Montreal (YMQ) 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 3 March 2026.

Round-trip from

C$ 384

One-way from

C$ 236

Popular in

March

Cheapest in

July

Average price

C$ 1,143

Good one-way deal

C$ 490 or less
American Airlines
  • American Airlines
  • 20/4-28/4
  • 2 total stops
  • 29h 39m total
  • Montreal to St. Louis
Search Deals
American Airlines
  • American Airlines
  • 8/4
  • 1 total stop
  • 12h 16m total
  • Montreal to St. Louis
Search Deals
High demand for flights, 7% potential price rise
Search Deals
Cheapest flight prices on average. 2% potential price decrease (C$ 35 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals
Price to beat on a one-way flight from Montreal (YMQ) to Lambert-St Louis.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Montreal 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 629,999 searches. Data last updated 3 March 2026.
Use the filters below to find and compare flights from Montreal to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 18/5

6:30 p.m.-8:25 p.m.

Nonstop2h 55m

Lambert-St Louis

Sun 24/5

7:05 a.m.-3:24 p.m.

2 stops7h 19m

C$ 582

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 30/3

4:55 p.m.-9:08 p.m.

1 stop5h 13m

Lambert-St Louis

Tue 31/3

6:15 a.m.-1:09 p.m.

1 stop5h 54m

C$ 603

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 12/4

6:45 p.m.-11:58 p.m.

1 stop6h 13m

Lambert-St Louis

Sun 19/4

7:25 a.m.-5:35 p.m.

1 stop9h 10m

C$ 608

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

7:00 a.m.-12:20 p.m.

1 stop6h 20m

Lambert-St Louis

Sat 16/5

6:04 p.m.-11:13 p.m.

1 stop4h 09m

C$ 608

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 31/3

4:55 p.m.-9:47 p.m.

1 stop5h 52m

Lambert-St Louis

Tue 7/4

11:15 a.m.-10:06 p.m.

2 stops9h 51m

C$ 610

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 20/4

6:00 a.m.-1:05 p.m.

1 stop8h 05m

Lambert-St Louis

Sat 25/4

1:03 p.m.-11:51 p.m.

1 stop9h 48m

C$ 610

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 15/4

6:35 p.m.-8:25 a.m.

2 stops14h 50m

Lambert-St Louis

Wed 22/4

6:30 a.m.-4:10 p.m.

2 stops8h 40m

C$ 610

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

7:00 a.m.-12:06 p.m.

1 stop6h 06m

Lambert-St Louis

Sat 16/5

7:05 a.m.-3:49 p.m.

2 stops7h 44m

C$ 625

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 1/5

7:00 a.m.-11:56 a.m.

1 stop5h 56m

Lambert-St Louis

Fri 8/5

7:15 a.m.-5:42 p.m.

1 stop9h 27m

C$ 630

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 15/4

6:50 a.m.-10:30 a.m.

3 stops28h 40m

C$ 268

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/3

Showing 1-10 of 21 resultsSorted by cheapest first
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Best time to book a flight from Montreal to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Montreal 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 to St. Louis

What is the cheapest month to book a flight from Montreal to St. Louis?

Currently, September is the cheapest month in which you can book a flight from Montreal to St. Louis (average of C$ 459). Flying from Montreal to St. Louis in January is currently the most expensive (average of C$ 875). 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 to St. Louis?

What’s the top layover airport for flights from Montreal to St. Louis?

Share of one-stop round-trip flights from Montreal to St. Louis chosen by Cheapflights users in the past 12 months, using the same layover each way.

Toronto (YYZ) – chosen by Cheapflights users on 50% of one-stop itineraries from Montreal to St. Louis on Cheapflights.

What’s the cheapest layover airport for flights from Montreal to St. Louis?

Average round-trip fare for 1-stop flights from Montreal to St. Louis, chosen by Cheapflights users in the past 12 months, with the same layover each way.

Chicago (ORD) is the most affordable 1-stop option, with an average round-trip price of C$ 641.

What’s the fastest layover option from Montreal to St. Louis?

Shortest average travel time for 1-stop one-way flights from Montreal to St. Louis, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Detroit (DTW) have the shortest average one-way travel time for 1-stop routes: 4h 41m.

Which airport typically offers the quickest layover for flights from Montreal to St. Louis?

Average layover duration for 1-stop one-way flights from Montreal to St. Louis, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Detroit (DTW) offer the fastest connection on this route, with an average layover time of 0h 58m.

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 3 March 2026.
Read reviews from past customers who have flown Air Canada from Montreal to St. Louis. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Air Canada
7.1
Good
10,770 reviews
Check prices

Entertainment

6.8

Overall

7.1

Crew

7.8

Boarding

7.3

Food

6.3

Comfort

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

YYZ - LAS

It's was great and the crew are very nice, captain has a smooth land on the runway 👍
Air Canada
7.1
Good
10,770 reviews
Air Canada
7.1
Good
10,770 reviews
Check prices

Entertainment

6.8

Overall

7.1

Crew

7.8

Boarding

7.3

Food

6.3

Comfort

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

YYZ - LAS

It's was great and the crew are very nice, captain has a smooth land on the runway 👍

Related info for your journey

Find useful and relevant information for your journey from Montreal 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?

    Most people fly into Lambert-St Louis (STL) if they book a flight to St. Louis from Montreal. On average, Lambert-St Louis has 0 inbound flights from Montreal per day from 2 airlines. Lambert-St Louis is conveniently located just 20.4 km from St. Louis’s city centre.

  • How long is the flight from Montreal to St. Louis?

    Airlines like American Airlines fly from Montreal to St. Louis in about 12h 16m. The time it takes to get you to your destination can typically vary by up to . The distance from Montreal to St. Louis is about 1556 km.

  • What are the cheapest airlines flying from Montreal to St. Louis round-trip?

    Currently priced at C$ 544, Air Canada will fly you from Montreal to St. Louis and back. In addition to Air Canada, many other airlines offer competitively priced options for your trip. Check Cheapflights for deals on WestJet for as low as C$ 732. You may be able to fly from Montreal to St. Louis for 37% less than the average price by searching for these airlines.

  • What are the cheapest flights from Montreal to St. Louis?

    Looking at all options, your cheapest flight can be booked for C$ 490. While the most popular route (Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis) can be booked for C$ 610 on average, our data indicates C$ 490 when flying from Montreal to St. Louis.

  • Can I find deals for flights from Montreal to St. Louis that include hotel bookings?

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

  • How can I find direct flights from Montreal to St. Louis?

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

  • Can I find deals for business class flights from Montreal to St. Louis?

    Yes. Cheapflights offers flight deals from Montreal 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 to St. Louis?

    Currently, September is the cheapest month in which you can book a flight from Montreal to St. Louis (average of C$ 459). Flying from Montreal to St. Louis in January is currently the most expensive (average of C$ 875). 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

Travelling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
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Top 2 airlines flying from Montreal to St. Louis

Discover the top 2 airlines that operate flights from Montreal 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 629,999 searches. Data last updated 3 March 2026.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapestC$ 544AverageC$ 824FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
WestJetCheapestC$ 732AverageC$ 940FlexibilityNo cancel feeOn-time60%
Search WestJet flights

Fly with Cheapflights

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How does Cheapflights help users find flights from Montreal to St. Louis?

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Why should you use Cheapflights to find cheap flight tickets from Montreal to St. Louis?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Montreal to St. Louis.

Can Cheapflights find flights from Montreal to St. Louis with no change fees?

Certainly. Search results for flights to St. Louis from Montreal shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Montreal to St. Louis become cheaper?

Not ready to book yet? You can track prices for flights from Montreal to St. Louis on Cheapflights with our Price Alert feature and get notified when better prices are available.

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