Cheap flights from Ontario to Chicago from $108

The month of October is another great option to travel to Chicago O'Hare Intl Airport, with average flight prices from Ontario averaging around $364.

The cheapest day to depart on your flight to Chicago O'Hare Intl Airport is on a Wednesday when prices can be found for as low as $404. This is often the case because there is less demand to fly during this day of the week. On the other hand, Sunday is the most expensive day to depart from Ontario because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $506.

Flying to Chicago O'Hare Intl Airport from Ontario in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $367 when looking at flights departing in the afternoon. Try not to purchase tickets at noon because they tend to be around $527. Of course, these prices can vary depending on the time of year and what airport you fly to.

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

You are more likely to see cheaper flights to Chicago O'Hare Intl Airport from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago O'Hare Intl Airport for around $409 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 Ontario for as low as $334 on momondo.

There are 4 cabin classes available to choose from on Ontario 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 42% on your flight if you consider stops on a Ontario to Chicago O'Hare Intl Airport flight.

As of September 2026, prices for Ontario to Chicago O'Hare Intl Airport flights are approximately 51% more expensive when compared to flights at the same time last year.

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

American Airlines, United Airlines and Frontier are the top three most popular airlines that fly to Chicago O'Hare Intl Airport from Ontario according to our data. American Airlines is the first choice among our users, with 43% of people opting to fly with this airline when traveling to Chicago O'Hare Intl Airport. Keep in mind that there are 7 different airlines that fly to Chicago O'Hare Intl Airport on a routine basis, so you have a few additional options to choose from.

Phoenix (PHX) was the most common stop: 73% of momondo users choosing 1-stop flights on this route connected there.

Flights via Salt Lake City (SLC) offer the lowest average round-trip price of $226.

Flights connecting via Las Vegas (LAS) have the shortest average one-way travel time: 5h 40m.

Las Vegas (LAS) has the shortest average layover time for this route: 0h 45m.