$60 Cheap Frontier Airlines flights San Diego (SAN) to Denver (DEN)

Use the "Price (lowest to highest)" filter on Expedia to look for cheap Frontier Airlines return flights from $103 from SAN to DEN. Affordable one-way fares from $60 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.

Start searching one to three months ahead of your departure date to get cheap fares on Frontier Airlines flights from San Diego Intl. Airport (SAN) 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.* Nail your timing, 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.

The earliest Frontier Airlines flight from SAN to DEN takes off at 6:25AM UTC-8, touching down at 9:56AM UTC-7. If you prefer to set off later, the last Frontier Airlines flight leaves SAN at 6:51PM UTC-8 and lands at DEN at 10:19PM UTC-7. Flying earlier is often a wise choice as morning and mid-morning flights are least 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.

A rewarding loyalty program and the ability to collect points through Frontier Miles are the start of the reasons to jet off from SAN to DEN with Frontier Airlines. Plus, when you join our One Key™ program, you can receive OneKeyCash™* in addition to Frontier Airlines's loyalty program earnings. It's yours to use wherever your next trip takes you.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.