$139 Cheap United flights Philadelphia (PHL) to San Antonio (SAT)

Apply the "Price (lowest to highest)" filter on Expedia to search for cheap United Airlines round-trip flights from $157 from PHL to SAT. Affordable one-way options from $139 are also available.**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 travel date to find cheap fares on United Airlines flights from Philadelphia Intl. Airport (PHL) to San Antonio Intl. Airport (SAT). 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.* Get the timing right, 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.

Search United Airlines's earliest flights from PHL to SAT by checking our "Early Morning" and "Morning" filters. Not only will you arrive sooner, early departures are also 20% less likely to be canceled.**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 collect points through United Mileage Plus are the start of the reasons to travel from PHL to SAT with United Airlines. Plus, when you sign up to Expedia's free One Key™ program, you can earn OneKeyCash™* on top of United Airlines's loyalty program earnings. You can put it toward your future trips.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.