The cheapest times to fly from YUL to STL are

  • January 1st to February 25th
  • August 20th to February 25th (except the weeks of December 17th and December 24th)

based on data collected exclusively by Champion Traveler across tens of millions of flights. Among all the dates above, the very cheapest time to fly from YUL to STL is late January. Prices can be as high as $504 for Sunday flights during late July, or as low as $228 for Tuesday flights around late January.


When to Fly to St. Louis

Flying from Montreal (YUL) to St. Louis, MO (STL) will usually cost between $237 to $423 per person if booking more than four weeks in advance. On average the very cheapest time to fly is late January with an average ticket price of $242. Due to high demand the most expensive time to fly is late July, with an average price of $407. Planning your trip to low-cost times can easily save you $165 on economy flights and even more on first-class flights. Generally, any price below $305 can be considered a good price for a round-trip YUL to STL flight.

See below for a graph of average weekly prices for the YUL to STL route. All prices are for round-trip tickets in USD.

YUL to STL Flight Prices

Compared to other flights, the YUL to STL flight is much cheaper than the average and costs much less than the average flight leaving from Montreal. The average price per mile (for a direct flight) is $0.2, which is below average.


Flight Prices by Day of the Week

Tuesday is usually the cheapest day to depart and return on this flight. Sundays are the most expensive days to fly out or take a return trip. Selecting flights on the least expensive days could save you up to $67 (18%) on this flight.

Departing prices are for round-trip flights returning on the day of departure. For example, a flight departing on Tuesday and returning a week later will cost an average of $280. Return trip prices are from the STL to YUL flight, and often highlight the quality of our data in showing the same trend.

Departing Prices by Day

Departure Day Prices

Return Trip Prices by Day

Return Day Prices


Nonstop Flights and Layovers

Travelers looking to fly from YUL to STL can generally find a 1-layover flight. Because there is not usually a direct flight option the real-world direct flight time of 2 hour 43 minutes may not be realistic.


Flight Questions Answered

Still have questions about flying from YUL to STL? We’ve got answers.

Which airlines fly this route?

You can find 8 major airlines flying this route most often: Air Canada, American, Avianca, Cape Air, Delta, Qantas, United, WestJet, and potentially more during busy seasons.

How far away is it from St Louis Lambert International Airport to Pierre Elliott Trudeau International Airport?

The distance between the two airports is roughly 968 miles or 1558 kilometers.

How long does it take to fly from YUL to STL?

The real-world flight time for a nonstop YUL to STL flight is about 2 hour 43 minutes.

How many flights go between Montreal and St. Louis, MO?

It depends on the day of the week and the date, but a typical day might have around 59 available flights from YUL to STL.


Airport Location Info


Departing Airport

Origination codeYUL
Origination airport namePierre Elliott Trudeau International Airport

Return Airport

Destination codeSTL
Destination airport nameSt Louis Lambert International Airport
CitySt. Louis, MO
Countrythe United States


Other Resources

Please note that while we’ve worked hard to analyzed tens of millions of flights to get you this data, we do not calculate current live prices or guarantee pricing. Please see our partners using the links above for current offers.