Cheap flights from St Louis to Chicago, United States (STL - CHI)

Flying from St Louis to Chicago can be expensive. Our search helps you compare cheap flights, airfare deals, and flight tickets across airlines and agencies so you can book at the best price.

We scan trusted travel agencies and airline booking systems for the route St Louis - Chicago (STL - CHI). We do not sell tickets or add fees - you choose where to buy.

Airfares vary by date, time, and airport. Use filters to find the best option by departure/arrival time, number of stops, airline or alliance, and booking channel.

If your dates are flexible, check the low-fare calendar to find the cheapest days. Booking round-trip in one order often reduces fees, and prices usually rise as departure approaches.

We also recommend you to look through the prices for return tickets from Chicago to St Louis.

Airfares found by our users in the past 24 hours

The cheapest flight from St Louis to Chicago is 12 551 on United Airlines, departing on 02/07/2026 - 18:57 and returning on 02/19/2026 - 04:40.
The price for these dates could change. Use search to get the best price.

Average round-trip airfares from St Louis to Chicago by months

MonthRound-Trip
January 202630.01 - 17.02from 17 499
February 202607.02 - 19.02from 12 551
March 2026find now
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Prices shown are based on searches from the last few days. Ticket prices can change and depend on availability at the time of booking.

Airlines are flying from St Louis to Chicago

Southwest Airlines
Find Flights to Chicago