When booking a flight to Chicago, the best deals can typically be found by booking in advance. However, the exact amount of time in advance that you should book can vary depending on a number of factors.
One of the most important factors to consider is the time of year that you plan to travel. If you are planning to travel during peak travel seasons, such as summer or the winter holidays, it is generally best to book your flight as far in advance as possible. This is because airlines tend to raise prices as the departure date approaches, and seats on popular flights can fill up quickly.