Cheap flights from St. Louis to Chicago from $59

The month of October is another great option to travel to Chicago O'Hare Intl Airport, with average flight prices from St. Louis averaging around $315.

The cheapest day to depart on your flight to Chicago O'Hare Intl Airport is on a Friday when prices can be found for as low as $697. This is often the case because there is less demand to fly during this day of the week. On the other hand, Wednesday is the most expensive day to depart from St. Louis because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $888.

Flying to Chicago O'Hare Intl Airport from St. Louis in the morning is the least expensive time of day to depart. momondo users have found prices as low as $627 when looking at flights departing in the morning. Try not to purchase tickets at noon because they tend to be around $1,164. Of course, these prices can vary depending on the time of year and what airport you fly to.

Fly from Lambert-St Louis to Chicago O'Hare Intl for the best Lambert-St Louis - Chicago O'Hare Intl flight prices

You are more likely to see cheaper flights to Chicago O'Hare Intl Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago O'Hare Intl Airport for around $353 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 St. Louis for as low as $97 on momondo.

There are 4 cabin classes available to choose from on St. Louis 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.

United Airlines, Delta, and Frontier are the most popular carriers operating from Lambert-St Louis to Chicago O'Hare Intl

United Airlines, American Airlines and Contour are the top three most popular airlines that fly to Chicago O'Hare Intl Airport from St. Louis according to our data. United Airlines is the first choice among our users, with 53% of people opting to fly with this airline when traveling to Chicago O'Hare Intl Airport. Keep in mind that there are 3 different airlines that fly to Chicago O'Hare Intl Airport on a routine basis, so you have a few additional options to choose from.

As of September 2026, 47 flights take off from St. Louis and land in Chicago O'Hare Intl Airport each day. The most common flight departure time for this route is 9:00AM, with 46% of daily flights taking off at noon.

The number of flights available between St. Louis and Chicago O'Hare Intl Airport is 329 per week as of September 2026. The most frequent departure day is Fri, with 21% of weekly flights leaving on this day.