$84 Cheap United flights Billings (BIL) to Phoenix (PHX)

Grab affordable round-trip United Airlines flights from $173 from BIL to PHX by sorting your results from "Price (lowest to highest)" on Expedia. Or look for bargains from $84 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.

Search for affordable United Airlines flights from Logan Intl. Airport (BIL) to Sky Harbor Intl. Airport (PHX) one to three months before your departure. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. No matter the fare type and itinerary, the best day to book a domestic flight is usually Sunday and the most expensive day is typically Monday. Passengers who book on a Sunday can save 6% on average compared to those who book on a Monday.**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 BIL to PHX with United Airlines, sort your results by "Morning" and "Early Morning." Booking an early flight generally 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.

Depart from BIL to PHX with United Airlines and you'll 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 may 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.