$64 Cheap Frontier Airlines flights Spokane (GEG) to Denver (DEN)

Make use of the "Price (lowest to highest)" filter on Expedia to find cheap Frontier Airlines round-trip flights from $108 from GEG to DEN. Affordable one-way fares from $64 are also on offer.**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 cheap Frontier Airlines flights from Spokane Intl. Airport (GEG) to Denver Intl. Airport (DEN) one to three months ahead of your departure date. 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 ideal day to book a domestic flight is usually Sunday and the most expensive 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.

Sort your results by "Early Morning" and "Morning" to see the earliest flights from GEG to DEN. Jetting off early means you're 20% 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.

Fly from GEG to DEN with Frontier Airlines and you can look forward to a range of benefits including a rewarding loyalty program. When you book through Expedia as a Frontier Miles and One Key™ member, you may 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.