$138 Cheap United flights Austin (AUS) to Philadelphia (PHL)

Finding cheap one-way United Airlines flights from AUS to PHL from $138 on Expedia is simple — just filter by "Price (lowest to highest)." Alternatively, check out our budget-friendly return fares from $208 for your next getaway.**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.

For cheap United Airlines fares from Austin-Bergstrom Intl. Airport (AUS) to Philadelphia Intl. Airport (PHL), start searching one to three months before your planned departure. Securing domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also impact the cost. Sunday is usually the most affordable, while Monday is often the most expensive for domestic flights. You can save 6% on average by choosing to book on a Sunday.**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.

Sort your results by "Early Morning" and "Morning" to find the earliest flights from AUS to PHL. Heading off early means you're less likely to experience cancellations.**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.

Fly from AUS to PHL with United Airlines and look forward to a range of perks including a rewarding loyalty program. When booking through Expedia as a United Mileage Plus and One Key™ member, you could 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.