Cheap flights from Ontario to Chicago from $104

The month of July is, on average, the cheapest month to fly to Chicago from Region of Ontario, with most prices found around $216. If you’re not able to fly to Chicago in July, then June is your next best option. Flight prices from Region of Ontario to Chicago during June average around $222.

The cheapest day to depart on your flight to Chicago is on a Thursday when prices can be found for as low as $420. This is often the case because there is less demand to fly during this day of the week. When flying out on a Monday, the most expensive travel day of the week, you can expect to see flight prices from Region of Ontario to Chicago for around $691.

Our most recent data shows that the best time of day to fly to Chicago is in the evening. Flights from Region of Ontario to Chicago during this time can be as low as $381. In contrast, the most expensive time of day to depart to Chicago is in the afternoon when prices are around $627.

Fly from Toronto Pearson Intl to Chicago O'Hare Intl for the best Ontario - Chicago flight prices

You are more likely to see cheaper flights to Chicago from Region of Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago for around $288 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago from Region of Ontario for as low as $195 on momondo.

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

United Airlines, Air Canada, and Porter Airlines are the most popular carriers operating from Ontario to Chicago

Air Canada, United Airlines and American Airlines are the top three most popular airlines that fly to Chicago from Region of Ontario according to our data. Air Canada is the first choice among our users, with 44% of people opting to fly with this airline when traveling 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.

The number of flights available between Region of Ontario and Chicago is 89 per day as of February 2026. The most frequent departure time is 6:00AM, with 49% of daily flights leaving at noon.

As of February 2026, 625 flights take off from Region of Ontario 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.