$126 Cheap United flights Portland (PDX) to Knoxville (TYS)

Apply the "Price (lowest to highest)" filter on Expedia to search for cheap United Airlines return flights from $249 from PDX to TYS. Affordable one-way fares from $126 are available too.**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 United Airlines flights from Portland Intl. Airport (PDX) to McGhee Tyson Airport (TYS). 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 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 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.

Find United Airlines's earliest flights from PDX to TYS by checking our "Early Morning" and "Morning" filters. Not only will you get to where you're going sooner, early departures also have a 20% less chance of being 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.

Journey from PDX to TYS with United Airlines and enjoy a range of perks including a rewarding loyalty program. When you book through Expedia as a United Mileage Plus and One Key™ member, you can also earn OneKeyCash™* to redeem on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.