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Cheap flights from Montreal to St. Louis from C$ 296

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 26/4. Fares are subject to change and may not be available on all flights or dates of travel.
YMQ — STL
16 Apr — 23 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 17 March 2026.

Tue 28/412:30 p.m.
YUL
-
STL
1 stop12h 16m
American Airlines
Tue 5/54:30 p.m.
STL
-
YUL
1 stop18h 14m
American Airlines
Deal found 14/3C$ 539
Tue 5/512:30 p.m.
YUL
-
STL
1 stop10h 49m
American Airlines
Sat 9/58:03 p.m.
STL
-
YUL
1 stop14h 41m
American Airlines
Deal found 15/3C$ 545
Sat 2/56:30 p.m.
YUL
-
STL
Nonstop2h 55m
Air Canada
Sun 3/51:00 p.m.
STL
-
YUL
Nonstop2h 35m
Air Canada
Deal found 14/3C$ 665
Sun 26/410:10 a.m.
YUL
-
STL
1 stop6h 15m
Air Canada
Sun 3/51:00 p.m.
STL
-
YUL
Nonstop2h 35m
Air Canada
Deal found 12/3C$ 683
Thu 16/412:30 p.m.
YUL
-
STL
1 stop12h 16m
American Airlines
Wed 29/48:03 p.m.
STL
-
YUL
1 stop14h 41m
American Airlines
Deal found 14/3C$ 685
Sun 19/47:45 a.m.
YUL
-
STL
1 stop6h 03m
American Airlines
Wed 29/47:05 a.m.
STL
-
YUL
2 stops14h 53m
American Airlines
Deal found 14/3C$ 697
Sat 2/512:30 p.m.
YUL
-
STL
1 stop10h 47m
American Airlines
Sun 3/58:03 p.m.
STL
-
YUL
1 stop14h 41m
American Airlines
Deal found 14/3C$ 700
Wed 15/49:30 a.m.
YUL
-
STL
1 stop10h 56m
Delta
Sat 18/45:59 p.m.
STL
-
YUL
1 stop4h 09m
Delta
Deal found 16/3C$ 701

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 17 March 2026.

Round-trip from

C$ 539

One-way from

C$ 296

Popular in

May

Cheapest in

July

Average price

C$ 990

Good one-way deal

C$ 491 or less
American Airlines
  • American Airlines
  • 28/4-5/5
  • 2 total stops
  • 30h 30m total
  • Montreal to St. Louis
Search Deals
26/4
  • 26/4
  • 2 total stops
  • 23h 50m total
  • Montreal to St. Louis
Search Deals
Highest demand for flights based on searches. 13% potential increase in price (C$ 188 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (C$ 46 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 17 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

Cheapest round-trip
Quickest round-trip

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 26/4

10:10 a.m.-3:25 p.m.

1 stop6h 15m

Lambert-St Louis

Sun 3/5

1:00 p.m.-4:35 p.m.

Nonstop2h 35m

C$ 683

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 15/4

9:30 a.m.-7:26 p.m.

1 stop10h 56m

Lambert-St Louis

Sat 18/4

5:59 p.m.-11:08 p.m.

1 stop4h 09m

C$ 701

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

6:10 a.m.-10:48 a.m.

1 stop5h 38m

Lambert-St Louis

Sat 16/5

7:45 a.m.-9:26 p.m.

1 stop12h 41m

C$ 713

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 15/4

6:00 a.m.-10:56 a.m.

1 stop5h 56m

Lambert-St Louis

Sat 18/4

9:16 a.m.-9:26 p.m.

1 stop11h 10m

C$ 713

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 5/5

2:20 p.m.-9:13 p.m.

2 stops7h 53m

Lambert-St Louis

Sat 9/5

1:24 p.m.-9:26 p.m.

1 stop7h 02m

C$ 728

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

6:00 a.m.-1:10 p.m.

1 stop8h 10m

Lambert-St Louis

Sat 16/5

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

1 stop4h 09m

C$ 730

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 21/5

6:00 a.m.-3:46 p.m.

2 stops10h 46m

Lambert-St Louis

Tue 26/5

9:23 a.m.-7:45 p.m.

2 stops9h 22m

C$ 730

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 20/4

6:45 p.m.-11:36 p.m.

1 stop5h 51m

Lambert-St Louis

Sat 25/4

5:35 p.m.-11:26 p.m.

1 stop4h 51m

C$ 731
Cheapest one-way

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 30/4

6:45 a.m.-6:50 a.m.

2 stops25h 05m

C$ 314

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 31/5

6:45 a.m.-12:21 a.m.

2 stops18h 36m

C$ 393

Flights are sorted by cheapest round-trip flights first.

Deals found on 16/3

Showing 1-10 of 17 resultsSorted by cheapest first
1
2

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$ 460). Flying from Montreal to St. Louis in January is currently the most expensive (average of C$ 876). 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 55% 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$ 642.

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 17 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
10,811 reviews
Check prices

Entertainment

6.8

Overall

7.1

Crew

7.8

Boarding

7.3

Food

6.3

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.
Air Canada
7.1
Good
10,811 reviews
Air Canada
7.1
Good
10,811 reviews
Check prices

Entertainment

6.8

Overall

7.1

Crew

7.8

Boarding

7.3

Food

6.3

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 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 Air Canada, Delta, and United Airlines fly from Montreal to St. Louis in about 5h 38m. The time it takes to get you to your destination can typically vary by up to 5h 18m. The distance from Montreal to St. Louis is about 1556 km. This flight may include one or multiple stops.

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

    Currently priced at C$ 593, 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$ 734. You may be able to fly from Montreal to St. Louis for 31% 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$ 491. While the most popular route (Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis) can be booked for C$ 701 on average, our data indicates C$ 491 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$ 460). Flying from Montreal to St. Louis in January is currently the most expensive (average of C$ 876). 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 17 March 2026.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapestC$ 593AverageC$ 830FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
WestJetCheapestC$ 734AverageC$ 942FlexibilityNo cancel feeOn-time60%
Search WestJet flights

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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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