$83 Cheap Frontier Airlines flights Salt Lake City (SLC) to St. Louis (STL)

You'll find affordable return Frontier Airlines flights from $154 from SLC to STL by sorting your results from "Price (lowest to highest)" on Expedia. Or look for options from $83 for a one-way journey.**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 before your departure to score cheap fares on Frontier Airlines flights from Salt Lake City Intl. Airport (SLC) to Lambert-St. Louis Intl. Airport (STL). You can save 25% by booking your domestic flight 34 to 86 days in advance versus 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.* Get the timing right, and you can enjoy significant savings on domestic flights.*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 departure from SLC to STL with Frontier Airlines, filter your search by "Early Morning" and "Morning." Booking 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.

Depart from SLC to STL with Frontier Airlines and you'll enjoy a host of benefits starting with a rewarding loyalty program. When you book through Expedia as a Frontier Miles and One Key™ member, you can also earn OneKeyCash™* to spend on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.