$80 Cheap American Airlines flights Atlanta (ATL) to St. Louis (STL)

Landing cheap one-way American Airlines flights from ATL to STL from $80 on Expedia couldn't be easier --- just filter by "Price (lowest to highest)." Or check out our affordable return fares from $125 for your next adventure.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Start searching one to three months ahead of your departure date to get cheap fares on American Airlines flights from Hartsfield-Jackson Atlanta Intl. Airport (ATL) to Lambert-St. Louis Intl. Airport (STL). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Time it well, and you can enjoy significant savings on domestic journeys.*Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

To find the earliest departures from ATL to STL with American Airlines, filter your results by "Morning" and "Early Morning." Choosing an early flight generally means cancellations are less likely.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.