Cheap flights from Montreal to Chicago from C$ 239

In general, October is the cheapest month to fly from Montreal to Chicago O'Hare Intl Airport. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around C$ 74. The month of August is another great option to travel to Chicago O'Hare Intl Airport, with average flight prices from Montreal averaging around C$ 118.

The cheapest day to depart on your flight to Chicago O'Hare Intl Airport is on a Thursday when prices can be found for as low as C$ 729. This is often the case because there is less demand to fly during this day of the week. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Montreal to Chicago O'Hare Intl Airport for around C$ 1,086.

In the afternoon is the cheapest time of day to fly from Montreal to Chicago O'Hare Intl Airport when you can find flight prices for as low as C$ 759. Flying to Chicago O'Hare Intl Airport in the afternoon is an ideal time because this is during off-peak travel hours. If you have a flexible travel schedule, then try to avoid flying at noon when prices are C$ 1,205 on average. Flights to Chicago O'Hare Intl Airport from Montreal at noon are generally more expensive because this time of day is more convenient for travellers’ schedules.

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

You are more likely to see cheaper flights to Chicago O'Hare Intl Airport from Montreal when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago O'Hare Intl Airport for around C$ 509 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago O'Hare Intl Airport from Montreal for as low as C$ 326 on momondo.

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

You could potentially save up to 7% on your flight if you consider stops on a Montreal to Chicago O'Hare Intl Airport flight.

As of July 2026, prices for Montreal to Chicago O'Hare Intl Airport flights are approximately 6% more expensive when compared to flights at the same time last year.

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

Air Canada, United Airlines and American Airlines are the top three most popular airlines that fly to Chicago O'Hare Intl Airport from Montreal according to our data. Air Canada is the first choice among our users, with 73% of people opting to fly with this airline when travelling to Chicago O'Hare Intl Airport. Keep in mind that there are 4 different airlines that fly to Chicago O'Hare Intl Airport on a routine basis, so you have a few additional options to choose from.

Toronto (YYZ) was the most common stop: 50% of momondo users choosing one-stop flights on this route connected there.

Flights via Toronto (YTZ) offer the lowest average round-trip price of C$ 397.

Flights connecting via Toronto (YTZ) have the shortest average one-way travel time: 5h 00m.

Toronto (YYZ) has the shortest average layover time for this route: 1h 49m.

As of July 2026, there are 25 flights per day flying from Montreal to Chicago O'Hare Intl Airport. The most common time of day flights depart is 6:00a.m., with 50% of flights taking off in the afternoon.

As of July 2026, 175 flights take off from Montreal and land in Chicago O'Hare Intl Airport each week. The most common flight departure day for this route is Wed, with 19% of weekly flights taking off on this day.