Cheap flights from Montreal to Chicago from C$ 142

The month of September is another great option to travel to Chicago, with average flight prices from Montreal averaging around C$ 379.

The cheapest day to depart on your flight to Chicago is on a Thursday when prices can be found for as low as C$ 679. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around C$ 1,024. These prices are subject to change though, so be sure to set up a Price Alert for flights to Chicago.

In the afternoon is the cheapest time of day to fly from Montreal to Chicago when you can find flight prices for as low as C$ 751. Flying to Chicago in the afternoon is an ideal time because this is during off-peak travel hours. At noon is when there is more demand to fly to Chicago, so prices are often more expensive at around C$ 1,153 per ticket.

Fly from Montreal Pierre Elliott Trudeau Intl to Chicago O'Hare Intl for the best Montreal - Chicago flight prices

You are more likely to see cheaper flights to Chicago from Montreal when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago for around C$ 465 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago from Montreal for as low as C$ 305 on momondo.

There are 4 cabin classes available to choose from on Montreal to Chicago flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Porter Airlines, United Airlines, and Delta are the most popular carriers operating from Montreal to Chicago

Air Canada, United Airlines and Porter Airlines are the top three most popular airlines that fly to Chicago from Montreal according to our data. Air Canada is the first choice among our users, with 65% of people opting to fly with this airline when travelling to Chicago. Keep in mind that there are 4 different airlines that fly to Chicago on a routine basis, so you have a few additional options to choose from.

As of March 2026, 22 flights take off from Montreal and land in Chicago each day. The most common flight departure time for this route is 3:00p.m., with 58% of daily flights taking off in the afternoon.

As of March 2026, 154 flights take off from Montreal and land in Chicago each week. The most common flight departure day for this route is Mon, with 15% of weekly flights taking off on this day.