$120 Cheap United flights St. Louis (STL) to West Palm Beach (PBI)

You can discover budget-friendly return United Airlines flights from $247 from STL to PBI by filtering your results from "Price (lowest to highest)" on Expedia. Or search for deals from $120 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.

Begin your search one to three months ahead of your travel date to find cheap fares on United Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Palm Beach Intl. Airport (PBI). 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 cut 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 trips.*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 STL to PBI with United Airlines, filter your search by "Early Morning" and "Morning." Choosing an early flight usually 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.

A rewarding loyalty program and the ability to rack up points through United Mileage Plus are the start of the reasons to jet off from STL to PBI with United Airlines. Plus, when you join our One Key™ program, you can earn OneKeyCash™* in addition to any airline loyalty program earnings. It's yours to spend on your next adventure.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.