From most locations, the cheapest flights to Chicago can be found during the month of October; however great deals can be found at other times.
On average, from most locations, when planning your trip to Chicago, try to book your flight in the region of 60 days in advance for the cheapest prices.
From most locations, the cheapest flights to Chicago are found on a Thursday. Booking a Sunday departure is usually the most expensive.
In general, when looking for the cheapest flight to Chicago, our data indicates that evening flights are the most cost-effective. midday flights tend to be the most expensive.