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Cheap flights from Montreal Pierre Elliott Trudeau Intl Airport 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 24/2. Fares are subject to change and may not be available on all flights or dates of travel.
YUL — STL
27 Feb — 6 Mar1
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 28 January 2026.

Tue 24/23:45 p.m.
YUL
-
STL
1 stop9h 03m
American Airlines
Tue 3/36:00 a.m.
STL
-
YUL
1 stop8h 04m
American Airlines
Deal found 25/1C$ 492
Mon 20/412:30 p.m.
YUL
-
STL
1 stop12h 18m
American Airlines
Sat 25/46:00 a.m.
STL
-
YUL
1 stop4h 44m
American Airlines
Deal found 26/1C$ 556
Thu 26/33:45 p.m.
YUL
-
STL
1 stop8h 59m
American Airlines
Mon 30/36:57 p.m.
STL
-
YUL
1 stop17h 48m
American Airlines
Deal found 25/1C$ 570
Thu 26/34:55 p.m.
YUL
-
STL
2 stops15h 07m
Multiple Airlines
Mon 30/37:47 a.m.
STL
-
YUL
1 stop15h 43m
Multiple Airlines
Deal found 25/1C$ 619
Thu 26/33:45 p.m.
YUL
-
STL
1 stop8h 59m
American Airlines
Sun 29/38:00 a.m.
STL
-
YUL
1 stop5h 58m
American Airlines
Deal found 27/1C$ 622
Thu 26/36:00 a.m.
YUL
-
STL
1 stop4h 46m
Delta
Mon 30/31:39 p.m.
STL
-
YUL
1 stop8h 34m
Delta
Deal found 26/1C$ 636
Sun 10/56:10 p.m.
YUL
-
STL
Nonstop2h 55m
Air Canada
Sat 16/57:30 a.m.
STL
-
YUL
1 stop6h 51m
Air Canada
Deal found 24/1C$ 640
Tue 24/36:00 a.m.
YUL
-
STL
1 stop4h 46m
Delta
Mon 30/35:25 p.m.
STL
-
YUL
1 stop5h 15m
Delta
Deal found 27/1C$ 645

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 28 January 2026.

Round-trip from

C$ 556

One-way from

C$ 261

Popular in

December

Cheapest in

May

Average price

C$ 1,036

Good one-way deal

C$ 490 or less
American Airlines
  • American Airlines
  • 20/4-25/4
  • 2 total stops
  • 17h 02m total
  • Montreal to St. Louis
Search Deals
24/2
  • 24/2
  • 3 total stops
  • 15h 51m total
  • Montreal to St. Louis
Search Deals
Highest demand for flights based on searches. 12% potential increase in price (C$ 160 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (C$ 33 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 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 28 January 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

Pierre Elliott Trudeau Intl

Fly to

St. Louis

Route

Depart

Return

Price

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 24/2

3:45 p.m.-11:48 p.m.

1 stop9h 03m

Lambert-St Louis

Tue 3/3

10:37 a.m.-10:56 p.m.

2 stops11h 19m

C$ 498

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 20/4

12:30 p.m.-11:48 p.m.

1 stop12h 18m

Lambert-St Louis

Sat 25/4

6:00 a.m.-11:44 a.m.

1 stop4h 44m

C$ 556

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 26/3

3:45 p.m.-11:44 p.m.

1 stop8h 59m

Lambert-St Louis

Mon 30/3

6:57 p.m.-1:45 p.m.

1 stop17h 48m

C$ 570

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 26/3

3:45 p.m.-11:44 p.m.

1 stop8h 59m

Lambert-St Louis

Sun 29/3

8:00 a.m.-2:58 p.m.

1 stop5h 58m

C$ 622

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

6:00 a.m.-9:30 a.m.

1 stop4h 30m

Lambert-St Louis

Sat 16/5

1:30 p.m.-11:58 p.m.

1 stop9h 28m

C$ 636

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 26/3

9:20 a.m.-4:31 p.m.

1 stop8h 11m

Lambert-St Louis

Mon 30/3

5:59 p.m.-11:13 p.m.

1 stop4h 14m

C$ 636

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sun 10/5

6:10 p.m.-8:05 p.m.

Nonstop2h 55m

Lambert-St Louis

Sat 16/5

7:30 a.m.-3:21 p.m.

1 stop6h 51m

C$ 640

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 24/3

6:00 a.m.-9:46 a.m.

1 stop4h 46m

Lambert-St Louis

Mon 30/3

5:25 p.m.-11:40 p.m.

1 stop5h 15m

C$ 645

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Tue 24/2

4:00 p.m.-6:51 a.m.

3 stops15h 51m

C$ 261

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 11/3

3:45 p.m.-11:44 p.m.

1 stop8h 59m

C$ 279

Flights are sorted by cheapest round-trip flights first.

Deals found on 25/1

Showing 1-10 of 15 results
1
2

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, March is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of C$ 536). Flying from Montreal Pierre Elliott Trudeau Intl Airport 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 Pierre Elliott Trudeau Intl Airport to St. Louis?

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 28 January 2026.
Get a feel of what it's like to fly with United Airlines,WestJet, andAir 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.
United Airlines
7.4
Good
9,208 reviews
Check prices

Entertainment

7.1

Food

6.6

Overall

7.4

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats
United Airlines
7.4
Good
9,208 reviews
United Airlines
7.4
Good
9,208 reviews
Check prices

Entertainment

7.1

Food

6.6

Overall

7.4

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats
WestJet
7.2
Good
3,251 reviews
United Airlines
7.4
Good
9,208 reviews
Check prices

Entertainment

7.1

Food

6.6

Overall

7.4

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats
Air Canada
7.1
Good
10,666 reviews
United Airlines
7.4
Good
9,208 reviews
Check prices

Entertainment

7.1

Food

6.6

Overall

7.4

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats

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 3 different airlines.

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

    For as low as C$ 498, American Airlines can have you in St. Louis from Montreal Pierre Elliott Trudeau Intl Airport in 9h 03m. Montreal Pierre Elliott Trudeau Intl Airport and St. Louis are separated by a distance of 1556 km.

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

    According to our current data, United Airlines (C$ 450), Air Canada (C$ 535), and WestJet (C$ 694) 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 46% 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$ 490. While the most popular route (Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis) can be booked for C$ 633 on average, our data indicates C$ 490 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, March is the cheapest month in which you can book a flight from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis (average of C$ 536). Flying from Montreal Pierre Elliott Trudeau Intl Airport 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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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.
Pierre Elliott Trudeau Intl to Kansas City flights
Pierre Elliott Trudeau Intl to Cape Girardeau flights

Top 3 airlines flying from Pierre Elliott Trudeau Intl to St. Louis

Discover the top 3 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 28 January 2026.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapestC$ 450AverageC$ 624FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Air CanadaCheapestC$ 535AverageC$ 749FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
WestJetCheapestC$ 694AverageC$ 991FlexibilityNo 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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