Find flights
When to book
Airlines
FAQs

Cheap flights from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis from C$ 280

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 4/12. Fares are subject to change and may not be available on all flights or dates of travel.
YUL — STL
26 Nov — 3 Dec1
1 adult
1 adult, Economy, 0 bags

Cheap 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 27 October 2025.

Round-trip from

C$ 521

One-way from

C$ 280

Popular in

August

Cheapest in

May

Average price

C$ 973

Good one-way deal

C$ 502 or less
10/12-13/12
  • 10/12-13/12
  • 3 total stops
  • 40h 07m total
  • Montreal to St. Louis
Search Deals
4/12
  • 4/12
  • 3 total stops
  • 17h 22m total
  • Montreal to St. Louis
Search Deals
Highest demand for flights based on searches. 11% potential increase in price (C$ 150 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (C$ 34 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals
Price to beat on a one-way flight from Montreal Pierre Elliott Trudeau Intl to Lambert-St Louis.
Search Deals

Find 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 27 October 2025.

Wed 10/126:45 a.m.YUL - STL
2 stops32h 07mMultiple Airlines
Sat 13/123:30 p.m.STL - YUL
1 stop8h 00mMultiple Airlines
Deal found 25/10C$ 521
Wed 10/126:45 a.m.YUL - STL
2 stops32h 07mMultiple Airlines
Wed 17/123:30 p.m.STL - YUL
1 stop8h 00mMultiple Airlines
Deal found 26/10C$ 544
Sat 22/116:45 a.m.YUL - STL
2 stops28h 18mMultiple Airlines
Sat 29/114:13 p.m.STL - YUL
1 stop7h 17mMultiple Airlines
Deal found 25/10C$ 620
Thu 11/125:10 p.m.YUL - STL
2 stops17h 37mMultiple Airlines
Thu 18/1211:51 a.m.STL - YUL
1 stop11h 54mMultiple Airlines
Deal found 27/10C$ 633
Sun 23/118:00 a.m.YUL - STL
2 stops35h 19mMultiple Airlines
Sun 30/1110:24 a.m.STL - YUL
1 stop13h 06mMultiple Airlines
Deal found 26/10C$ 684
Wed 26/113:49 p.m.YUL - STL
1 stop17h 20mAmerican Airlines
Fri 28/118:40 a.m.STL - YUL
1 stop5h 29mAmerican Airlines
Deal found 25/10C$ 705
Wed 10/129:35 a.m.YUL - STL
1 stop7h 17mDelta
Wed 17/129:50 a.m.STL - YUL
1 stop8h 04mDelta
Deal found 26/10C$ 723
Wed 10/129:35 a.m.YUL - STL
1 stop11h 42mDelta
Sat 13/125:00 p.m.STL - YUL
1 stop5h 32mDelta
Deal found 25/10C$ 726
Fri 5/124:45 p.m.YUL - STL
1 stop5h 02mDelta
Fri 2/16:05 a.m.STL - YUL
1 stop6h 44mDelta
Deal found 27/10C$ 744
Wed 10/128:25 a.m.YUL - STL
2 stops11h 52mUnited Airlines
Sat 13/126:42 p.m.STL - YUL
2 stops17h 04mUnited Airlines
Deal found 25/10C$ 750

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 27 October 2025.
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

Wed 10/12

6:45 a.m.-1:52 p.m.

2 stops32h 07m

Lambert-St Louis

Sat 13/12

3:30 p.m.-12:30 a.m.

1 stop8h 00m

C$ 521

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sat 17/1

6:00 a.m.-2:28 p.m.

1 stop9h 28m

Lambert-St Louis

Sat 24/1

11:20 a.m.-9:17 p.m.

1 stop8h 57m

C$ 546

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 19/2

3:45 p.m.-9:27 a.m.

1 stop18h 42m

Lambert-St Louis

Mon 23/2

6:04 a.m.-3:00 p.m.

1 stop7h 56m

C$ 596

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sat 22/11

6:45 a.m.-10:03 a.m.

2 stops28h 18m

Lambert-St Louis

Sat 29/11

4:13 p.m.-12:30 a.m.

1 stop7h 17m

C$ 620

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 10/12

9:35 a.m.-3:52 p.m.

1 stop7h 17m

Lambert-St Louis

Wed 17/12

9:50 a.m.-6:54 p.m.

1 stop8h 04m

C$ 723

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Wed 10/12

9:35 a.m.-8:17 p.m.

1 stop11h 42m

Lambert-St Louis

Sat 13/12

5:00 p.m.-11:32 p.m.

1 stop5h 32m

C$ 726

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Fri 5/12

4:45 p.m.-8:47 p.m.

1 stop5h 02m

Lambert-St Louis

Fri 2/1

6:05 a.m.-1:49 p.m.

1 stop6h 44m

C$ 744

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 11/12

5:25 p.m.-9:47 a.m.

3 stops17h 22m

C$ 305

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 4/12

6:45 a.m.-9:47 a.m.

2 stops28h 02m

C$ 318

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Thu 4/12

6:00 a.m.-1:53 p.m.

1 stop8h 53m

C$ 399

Flights are sorted by cheapest round-trip flights first.

Deals found on 26/10

Showing 1-10 of 16 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$ 549). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in August is currently the most expensive (average of C$ 814). 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 YUL to STL?

Find hourly flight availability from Pierre Elliott Trudeau Intl 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 27 October 2025.

It’s optimal to fly from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in the morning. By choosing this option you can save up to 26% on the cost of your flight, compared to a flight in the evening.

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 27 October 2025.
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
8,997 reviews
Check prices

Food

6.6

Crew

8.1

Boarding

7.7

Overall

7.4

Entertainment

7.1

Comfort

7.3

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
United Airlines
7.4
Good
8,997 reviews
United Airlines
7.4
Good
8,997 reviews
Check prices

Food

6.6

Crew

8.1

Boarding

7.7

Overall

7.4

Entertainment

7.1

Comfort

7.3

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
WestJet
7.2
Good
3,148 reviews
United Airlines
7.4
Good
8,997 reviews
Check prices

Food

6.6

Crew

8.1

Boarding

7.7

Overall

7.4

Entertainment

7.1

Comfort

7.3

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Air Canada
7.1
Good
10,370 reviews
United Airlines
7.4
Good
8,997 reviews
Check prices

Food

6.6

Crew

8.1

Boarding

7.7

Overall

7.4

Entertainment

7.1

Comfort

7.3

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000

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$ 546, United Airlines can have you in St. Louis from Montreal Pierre Elliott Trudeau Intl Airport in 9h 28m. 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$ 549), United Airlines (C$ 600), and WestJet (C$ 750) 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 33% less than the average price by searching for these airlines.

  • What are the most reliable airlines from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis?

    Before booking your flight to St. Louis from Montreal Pierre Elliott Trudeau Intl Airport, check out the most reliable airlines to get you to your destination on time: Sun Country Air (100%), Air Canada (73%), Jazz( 73%).

  • 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$ 502. While the most popular route (Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis) can be booked for C$ 397 on average, our data indicates C$ 502 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$ 549). Flying from Montreal Pierre Elliott Trudeau Intl Airport to St. Louis in August is currently the most expensive (average of C$ 814). 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
Chesterfield
St. Peters

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

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 27 October 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapestC$ 549AverageC$ 754FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
United AirlinesCheapestC$ 600AverageC$ 639FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
WestJetCheapestC$ 750AverageC$ 1,066FlexibilityNo 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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.