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Cheap flights from Montreal to St. Louis from C$ 290

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 29/7. Fares are subject to change and may not be available on all flights or dates of travel.
YMQ — STL
17 Jun — 24 Jun1
1 adult

Cheap 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 12 June 2025.

Round-trip from

C$ 455

One-way from

C$ 290

Popular in

May

Cheapest in

July

Average price

C$ 722

Good round-trip deal

C$ 1,098 or less

Good one-way deal

C$ 490 or less
American Airlines
  • American Airlines
  • 25/9-29/9
  • 2 total stops
  • 18h 30m total
  • Montreal to St. Louis
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29/7
  • 29/7
  • 2 total stops
  • 28h 44m total
  • Montreal to St. Louis
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Highest demand for flights based on searches. 7% potential increase in price (C$ 81 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease (C$ 30 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Price to beat on a round-trip flight from Montreal (YMQ) to Lambert-St Louis.
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Price to beat on a one-way flight from Montreal (YMQ) to Lambert-St Louis.
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Find flight deals from Montreal to St. Louis

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 12 June 2025.

Thu 25/912:30 p.m.YUL - STL
1 stop8h 55mAmerican Airlines
Mon 29/95:55 a.m.STL - YUL
1 stop9h 35mAmerican Airlines
Deal found 11/6C$ 455
Thu 10/71:10 p.m.YUL - STL
2 stops21h 42mMultiple Airlines
Thu 17/710:47 a.m.STL - YUL
3 stops26h 03mMultiple Airlines
Deal found 12/6C$ 537
Thu 28/86:00 a.m.YUL - STL
2 stops11h 06mDelta
Tue 2/912:00 p.m.STL - YUL
1 stop8h 48mDelta
Deal found 11/6C$ 626
Mon 23/68:00 a.m.YUL - STL
1 stop5h 36mAir Canada
Sun 29/61:30 p.m.STL - YUL
Nonstop2h 30mAir Canada
Deal found 10/6C$ 643
Thu 19/64:30 p.m.YUL - STL
1 stop5h 45mUnited Airlines
Thu 26/68:00 a.m.STL - YUL
1 stop8h 26mUnited Airlines
Deal found 12/6C$ 733
Thu 25/96:45 a.m.YUL - STL
2 stops28h 55mWestJet
Mon 29/91:30 p.m.STL - YUL
2 stops10h 07mWestJet
Deal found 10/6C$ 861

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 12 June 2025.
Use the filters below to find and compare flights from Montreal to St. Louis that are best for you.

Fly from

Montreal

Fly to

St. Louis

Route

Depart

Return

Price

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 25/9

12:30 p.m.-8:25 p.m.

1 stop8h 55m

Lambert-St Louis

Mon 29/9

5:55 a.m.-4:30 p.m.

1 stop9h 35m

C$ 455

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 10/7

1:10 p.m.-9:52 a.m.

2 stops21h 42m

Lambert-St Louis

Thu 17/7

10:47 a.m.-1:50 p.m.

3 stops26h 03m

C$ 537

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 28/8

6:00 a.m.-4:06 p.m.

2 stops11h 06m

Lambert-St Louis

Tue 2/9

12:00 p.m.-9:48 p.m.

1 stop8h 48m

C$ 626

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 23/6

8:00 a.m.-12:36 p.m.

1 stop5h 36m

Lambert-St Louis

Sun 29/6

1:30 p.m.-5:00 p.m.

Nonstop2h 30m

C$ 643

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 6/8

6:10 p.m.-8:00 p.m.

Nonstop2h 50m

Lambert-St Louis

Mon 18/8

8:00 a.m.-5:26 p.m.

1 stop8h 26m

C$ 744

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 25/9

6:45 a.m.-10:40 a.m.

2 stops28h 55m

Lambert-St Louis

Mon 29/9

1:30 p.m.-12:37 a.m.

2 stops10h 07m

C$ 861

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 29/7

6:45 a.m.-10:29 a.m.

2 stops28h 44m

C$ 290

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 19/9

5:15 p.m.-9:26 a.m.

1 stop17h 11m

C$ 301

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 4/7

6:00 a.m.-3:17 p.m.

1 stop10h 17m

C$ 350

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 14/9

6:10 p.m.-7:57 p.m.

Nonstop2h 47m

C$ 417

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/6

Showing 1-10 of 11 results
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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, January is the cheapest month in which you can book a flight from Montreal to St. Louis (average of C$ 365). Flying from Montreal to St. Louis in September is currently the most expensive (average of C$ 491). 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 YMQ to STL?

Find hourly flight availability from Montreal 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 12 June 2025.

Unlike in the evening, when flights are generally more expensive, you can save up to 14% on flights from Montreal to St. Louis by exploring options for tickets in the morning.

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 56.0 - 119.0 mm per month. May is typically the wettest month, when rainfall can reach 119.0 mm. February is typically the driest time to visit St. Louis when rainfall is around 56.0 mm.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 27.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 0.0 C).

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 12 June 2025.
Delta
8.0
Very good
7,950 reviews
Check prices

Entertainment

7.9

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Delta
8.0
Very good
7,950 reviews
Delta
8.0
Very good
7,950 reviews
Check prices

Entertainment

7.9

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
United Airlines
7.4
Good
8,790 reviews
Delta
8.0
Very good
7,950 reviews
Check prices

Entertainment

7.9

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,950 reviews
Check prices

Entertainment

7.9

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
WestJet
7.2
Good
2,868 reviews
Delta
8.0
Very good
7,950 reviews
Check prices

Entertainment

7.9

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Air Canada
7.1
Good
9,531 reviews
Delta
8.0
Very good
7,950 reviews
Check prices

Entertainment

7.9

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

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 1 inbound flight from Montreal per day from 3 airlines. Lambert-St Louis is conveniently located just 20.4 km from St. Louis’s city centre.

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

    Currently priced at C$ 455, American Airlines will fly you from Montreal to St. Louis and back. In addition to American Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Delta and Air Canada - these airlines can fly you to your destination from C$ 626 and C$ 643, respectively. 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 airlines to fly from Montreal to St. Louis one-way?

    To fly one-way, consider booking your trip with American Airlines, which is currently one of the cheapest options available, starting at C$ 301. Delta flights start at C$ 350 while deals on Air Canada start at C$ 417 one-way.

  • What are the most reliable airlines from Montreal to St. Louis?

    Before booking your flight to St. Louis from Montreal, check out the most reliable airlines to get you to your destination on time: Jazz (100%), Air Canada (79%), United Airlines( 59%).

  • 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$ 581 on average our data indicates C$ 799 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, January is the cheapest month in which you can book a flight from Montreal to St. Louis (average of C$ 365). Flying from Montreal to St. Louis in September is currently the most expensive (average of C$ 491). 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 Montreal?

Book flights to Montreal if you plan to visit one of these locations
Chesterfield
St. Peters

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Top 3 airlines flying from Montreal to St. Louis

Discover the top 3 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 12 June 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapestC$ 536AverageC$ 733FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
United AirlinesCheapestC$ 586AverageC$ 738FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
WestJetCheapestC$ 733AverageC$ 1,010FlexibilityNo 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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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.

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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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