$109 Cheap United flights Buffalo (BUF) to Denver (DEN)

Apply the “Price (lowest to highest)” filter on Expedia to search for cheap United Airlines round-trip flights from $217 from BUF to DEN. Affordable one-way fares from $109 are also available.**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.

January is one of the most affordable months to fly to Denver with United Airlines. You could also find great prices on one-way and round-trip tickets in November.

Search for cheap United Airlines flights from Buffalo Niagara Intl. Airport (BUF) to Denver Intl. Airport (DEN) one to three months ahead of your day of 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 class and journey, the best day to book a domestic flight is generally Sunday and the most expensive is typically Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel 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.

Click on the “Nonstop” filter when searching for direct United Airlines flights from BUF to DEN. You can also compare other carriers offering the same nonstop journey.

To find the earliest departures from BUF to DEN with United Airlines, filter your search by “Early Morning” and “Morning.” Booking an early flight generally means 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.

Denver Intl. Airport (DEN) is the primary Denver gateway for United Airlines flights from Buffalo Niagara Intl. Airport (BUF).

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

It’s generally possible to cancel or modify your flight, although there may be a charge if your booking was made over 24 hours ago. Need to keep your options open? Use our “Changes included” and “No cancel fee” filters to find flights that won’t penalize you if you need to adjust your plans. To update your itinerary, head to “Trips,” select your flight and click on “Manage Booking” for more details.