$540 Cheap United flights London (LHR) to Knoxville (TYS)

You'll find budget-friendly return United Airlines flights from $808 from LHR to TYS by sorting your results from "Price (lowest to highest)" on Expedia. Or look for bargains from $540 for a one-way trip.**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.

To discover affordable flights from LHR to TYS with United Airlines, start your search about one month before your intended departure. You can save 17% when you lock in your international tickets 18 to 29 days ahead instead of booking four to five months in advance. Another good tip? Booking on Sunday can lead to average savings of 17% compared to Friday (the most expensive day).**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.

Filter your results by "Early Morning" and "Morning" to see the earliest flights from LHR to TYS. Taking off early means flight 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.

Journey from LHR to TYS with United Airlines and you'll enjoy a range of benefits starting with a rewarding loyalty program. When booking through Expedia as a United Mileage Plus 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.