Cheap Flights from Montreal to St Louis

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Flight deals from Montreal to St Louis

Looking for a cheap last-minute deal or the best return flight from Montreal to St Louis? Find the lowest prices on one-way and return tickets right here.

Find the cheapest month to fly from Montreal to St Louis

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Montreal to St Louis flights are currently cheapest in May.

Direct flights from Montreal to St Louis

Montreal to St Louis: Alternative routes

Compare routes from Montreal to St Louis below. You may find an airport to fly into that's cheaper, faster, or easier than St Louis.

Montreal to St Louis: Flight information

The things to know before you go.
Cheapest flight found$691
Cheapest month to flyMay
Average flight time2 hrs, 48 mins
Most popular airlineAir Canada
Average flights per week40

Finding cheap flights from Montreal to St Louis: Frequently asked questions

The best price we found for a return flight from Montreal to St Louis is $691. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
2 hours and 48 minutes is the average flight time from Montreal to St Louis.
Air Canada, United and Jazz Air fly direct from Montreal to St Louis.
As of February 2026, there are 40 flights per week flying from Montreal to St Louis.
The cheapest month to fly from Montreal to St Louis is usually May.
After crunching the numbers on our flight calendar, we found that it is currently cheapest to fly from Montreal to St Louis Airport on Wednesday, 6 May 2026.
Yes – the average flight time is 2 hours and 48 minutes.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to St Louis but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.
We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to St Louis is around 40 days in advance, so don’t leave your flight to the last minute.

Travelling from Montreal to Lambert-St. Louis International Airport (STL): What you need to know

  • Montreal-Pierre Elliott Trudeau International Airport (YUL) is Montreal's main airport. Explore your options for booking a flight from Montreal to Lambert-St. Louis International Airport (STL) taking off from here.

  • Expect to be in the air for 2 hours 50 minutes. That's the average journey time for a direct Montreal to Lambert-St. Louis International Airport flight.

  • St Louis is one hour behind Montreal. Lambert-St. Louis International Airport is located in St Louis, which operates on the UTC-5 timezone.

  • Take your pick of 3 direct services every week between Montreal-Pierre Elliott Trudeau International Airport (YUL) and Lambert-St. Louis International Airport (STL). This is the most popular route, with Air Canada offering a 6:10pm departure from YUL to STL.

  • Leave enough time to make your flight from Montreal to STL. As a general rule, turn up at least two hours before international departures and an hour ahead for domestic flights.

  • In peak travel periods, expect extended wait times and show up earlier. Aim for at least two hours ahead for domestic flights and up to four hours for international journeys.

Airports in Montreal

Montreal-Pierre Elliott Trudeau International Airport (YUL)

  • Montreal-Pierre Elliott Trudeau International Airport (YUL) offers an easy route to your destination. Nonstop flights from Montreal to Lambert-St. Louis International Airport (STL) leave from this terminal.

  • You can book a direct flight from Montreal to Lambert-St. Louis International Airport with Air Canada. This leading airline operates services from YUL.

  • The most frequently booked airline between YUL and STL is Air Canada.

  • Located around 26 kilometres from central Montreal, YUL can be reached in about 25 minutes by car (depending on traffic). The journey by public transport will take roughly 45 minutes.

  • Want a relaxed start to your trip? Stay near Montreal-Pierre Elliott Trudeau International Airport. Whether you've booked an early flight from Montreal to Lambert-St. Louis International Airport or prefer not to feel hurried, these hotels are just the thing:

  • Of the flights that depart from Montreal-Pierre Elliott Trudeau International Airport, 64.89% arrive as scheduled at their destination.

  • YUL's address is 975 Romeo Vachon Street North.

St. Hubert Airport (YHU)

  • You can arrive at YHU from central Montreal in about 35 minutes by car (depending on traffic). The ride by public transport takes roughly 1 hour 45 minutes to travel the 40 kilometres or so.

  • Want to enjoy an extra night away before catching your Montreal to STL flight? Kick back in a hotel near St. Hubert Airport before your adventure officially begins. These stays have a room with your name on it:

About Lambert-St. Louis International Airport (STL)

Getting from Lambert-St. Louis International Airport (STL) to central St Louis

  • Central St Louis is about 16 kilometres from Lambert-St. Louis International Airport. Journey times by car hire or cab will vary based on time of day and traffic conditions, so do some research ahead of your trip.

  • It typically takes 35 minutes to get there using public transport.

How to find the cheapest flights from Montreal to Lambert-St. Louis International Airport (STL)

  • $339 is currently the lowest price for a one-way ticket from Montreal to Lambert-St. Louis International Airport. Return flights start at $691. These fares may change depending on availability.

  • To pick up cheap flights from Montreal to STL, book ahead. Airlines tend to offer their most competitively priced fares when tickets are first released.

  • Cheap Montreal to Lambert-St. Louis International Airport tickets are easier to find if you're not locked into specific dates. Use the 'Whole month' tool to compare fares across every month and then fly out on the cheapest day.

  • Finding a cheap flight ticket from Montreal to STL is easy with Price Alerts. Simply set up one of these automatic alerts and we'll let you know when the price has dropped.

  • Tailor your trip using filters. Pick your departure and arrival times, total journey duration and airlines. You can also sort the results by 'Fastest,' 'Cheapest' or 'Best' flights from Montreal to Lambert-St. Louis International Airport.

The best time to fly from Montreal to Lambert-St. Louis International Airport (STL)

  • Think about your travel style when deciding the best time to fly. April is the quietest month to go to St Louis. July is when most people book flights from Montreal to Lambert-St. Louis International Airport (STL), which may be perfect if you're chasing more excitement.

  • The warmest month in St Louis is July, with temperatures ranging between 17ºC and 33ºC. Lock in your Montreal to STL flight ticket then if that's your ideal forecast.

  • If you like travelling in cooler conditions, search for a cheap ticket from Montreal to Lambert-St. Louis International Airport in January when temperatures are between -8ºC and 7ºC.

More about St Louis

Explore more of the United States

  • St Louis has loads to offer, but there are so many other parts of the United States you'll want to see. About 257 kilometres east of St Louis, a trip to Evansville will keep your itinerary busy. Don't miss top attractions like Mesker Park Zoo, Riverfront Park and Evansville Zoological Society.

  • Around 177 kilometres west of St Louis, Columbia is another favourite stop in the United States. Start your sightseeing at Sentinel Park, Museum of Art and Archaeology and Bur Oak Brewing Company.

Prices shown on this page are estimated lowest prices only. Found in the last 45 days.