Cheap United flights Flagstaff (FLG) to Denver (DEN)

Finding cheap one-way United Airlines flights from FLG to DEN on Expedia couldn't be easier — just filter by "Price (lowest to highest)." Or check out our budget-friendly return fares for your next exciting 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.

Start searching one to three months ahead of your travel date to get cheap fares on United Airlines flights from Flagstaff Pulliam Field Airport (FLG) to Denver Intl. Airport (DEN). 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 reduce 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 your timing right, and you can enjoy significant savings on domestic trips.*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 "Morning" and "Early Morning" to see the earliest flights from FLG to DEN. Leaving 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.

Offering a rewarding loyalty program, United Airlines is a top choice for many travelers heading from FLG to DEN. Plus, as a United Mileage Plus and One Key™ member booking through Expedia, you could earn OneKeyCash™* on eligible flights along with your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.