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Cheap flights from Montreal Pierre Elliott Trudeau Intl Airport 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.
YUL — STL
15 Apr — 22 Apr1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Pierre Elliott Trudeau Intl to St. Louis

Enter your travel dates to find the best prices.

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 16 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 12/3C$ 536
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$ 541
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$ 546
Wed 15/41:20 p.m.
YUL
-
STL
1 stop8h 53m
United Airlines
Sat 18/48:21 a.m.
STL
-
YUL
1 stop8h 09m
United Airlines
Deal found 11/3C$ 597
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$ 667
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$ 685
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$ 686
Sun 19/412:30 p.m.
YUL
-
STL
1 stop12h 16m
American Airlines
Wed 29/44:30 p.m.
STL
-
YUL
1 stop18h 14m
American Airlines
Deal found 14/3C$ 698
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$ 701

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 16 March 2026.

Round-trip from

C$ 536

One-way from

C$ 296

Popular in

December

Cheapest in

April

Average price

C$ 756

Good one-way deal

C$ 492 or less
American Airlines
  • American Airlines
  • 20/4-25/4
  • 2 total stops
  • 29h 39m 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. 10% potential increase in price (C$ 138 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (C$ 31 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 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 629,999 searches. Data last updated 16 March 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

Wed 15/4

1:20 p.m.-9:13 p.m.

1 stop8h 53m

Lambert-St Louis

Sat 18/4

8:21 a.m.-5:30 p.m.

1 stop8h 09m

C$ 597

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$ 685

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$ 715

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

6:00 a.m.-9:29 a.m.

1 stop4h 29m

Lambert-St Louis

Sat 16/5

5:36 p.m.-11:41 p.m.

1 stop5h 05m

C$ 716
Quickest round-trip

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

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

Nonstop2h 55m

Lambert-St Louis

Sat 16/5

7:05 a.m.-1:21 p.m.

1 stop5h 16m

C$ 720

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 15/4

9:30 a.m.-4:24 p.m.

1 stop7h 54m

Lambert-St Louis

Sat 18/4

3:25 p.m.-11:26 p.m.

1 stop7h 01m

C$ 730

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$ 730

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 10/8

10:10 a.m.-2:02 p.m.

1 stop4h 52m

Lambert-St Louis

Sun 16/8

8:55 a.m.-3:22 p.m.

1 stop5h 27m

C$ 731

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 21/5

9:45 a.m.-3:46 p.m.

1 stop7h 01m

Lambert-St Louis

Tue 26/5

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

2 stops9h 22m

C$ 731

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 20/4

6:00 a.m.-9:42 a.m.

1 stop4h 42m

Lambert-St Louis

Sat 25/4

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

1 stop4h 09m

C$ 735

Flights are sorted by cheapest round-trip flights first.

Deals found on 16/3

Showing 1-10 of 21 resultsSorted by cheapest first
1
2
3

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, September is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of C$ 461). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in January is currently the most expensive (average of C$ 878). 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.

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 16 March 2026.
Get a feel of what it's like to fly with WestJet and Air Canada from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
WestJet
7.2
Good
3,295 reviews
Check prices

Food

6.2

Crew

7.9

Boarding

7.4

Overall

7.2

Entertainment

6.1

Comfort

7.0

Reviews

1 / 20
10.0
Excellent

Joseph,Feb 2026

YYJ - YEG

Is just a domestic flight can't complain at all..but everything is great..
WestJet
7.2
Good
3,295 reviews
WestJet
7.2
Good
3,295 reviews
Check prices

Food

6.2

Crew

7.9

Boarding

7.4

Overall

7.2

Entertainment

6.1

Comfort

7.0

Reviews

1 / 20
10.0
Excellent

Joseph,Feb 2026

YYJ - YEG

Is just a domestic flight can't complain at all..but everything is great..
Air Canada
7.1
Good
10,805 reviews
WestJet
7.2
Good
3,295 reviews
Check prices

Food

6.2

Crew

7.9

Boarding

7.4

Overall

7.2

Entertainment

6.1

Comfort

7.0

Reviews

1 / 20
10.0
Excellent

Joseph,Feb 2026

YYJ - YEG

Is just a domestic flight can't complain at all..but everything is great..

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?

    Located just 20.4 km from the city centre, Lambert-St Louis is the airport most travellers will use when flying to St. Louis from Montreal Pierre Elliott Trudeau Intl. Booking flights from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis (STL) should be relatively easy as there are 0 daily inbound flights from Montreal Pierre Elliott Trudeau Intl from 2 different airlines.

  • How long is the flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis?

    For as low as C$ 716, United Airlines can have you in St. Louis from Montreal Pierre Elliott Trudeau Intl Airport in 4h 29m. Montreal Pierre Elliott Trudeau Intl Airport and St. Louis are separated by a distance of 1556 km. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

  • What are the cheapest airlines flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis round-trip?

    According to our current data, Air Canada (C$ 594), and WestJet (C$ 735) offers the cheapest pricing from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis. You may be able to fly from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis for 30% less than the average price by searching for these airlines.

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

    Looking at all options, your cheapest flight can be booked for C$ 492. While the most popular route (Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis) can be booked for C$ 674 on average, our data indicates C$ 492 when flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis.

  • 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, September is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of C$ 461). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in January is currently the most expensive (average of C$ 878). 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

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Book flights to St. Louis if you plan to visit one of these locations
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Alternative routes for Pierre Elliott Trudeau Intl to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
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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 629,999 searches. Data last updated 16 March 2026.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapestC$ 594AverageC$ 831FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
WestJetCheapestC$ 735AverageC$ 944FlexibilityNo cancel feeOn-time60%
Search WestJet flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Pierre Elliott Trudeau Intl to St. Louis?

Cheapflights makes it easy to find Pierre Elliott Trudeau Intl to St. Louis flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

Why should you use Cheapflights to find cheap flight tickets from Pierre Elliott Trudeau Intl to St. Louis?

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Pierre Elliott Trudeau Intl to St. Louis for you. Better yet — we are completely free to use.

Can Cheapflights find flights from Pierre Elliott Trudeau Intl to St. Louis with no change fees?

Need flexible booking options for your flight to St. Louis from Pierre Elliott Trudeau Intl? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from Pierre Elliott Trudeau Intl to St. Louis become cheaper?

Yes, Cheapflights offers price alerts on Pierre Elliott Trudeau Intl to St. Louis flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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