Flights San Francisco → Denver — September 21, 2026

One way · Economy · 1 adult · price per person

The cheapest itinerary observed for Monday, September 21, 2026 on the San Francisco–Denver route: 1 stop itinerary (2 flights) via Dallas/Fort Worth (DFW), from San Francisco International (SFO) to Denver International (DEN), first flight Frontier Airlines F92930, departs 11:58 PM, arrives 8:15 AM the next day, total travel time 7h 17m including layovers, flight time 6h 5m (layovers excluded), $130 per person. Fare as listed by Aviasales: carry-on bag not included (personal item only), checked bag not included, changes not allowed, non-refundable. Price found in an Aviasales search on September 6, 2026 and read by AirSource on September 10, 2026, 20:48 UTC: it is not guaranteed and is confirmed on Aviasales at booking time. The cheapest direct flight observed: Frontier Airlines F91094, from San Francisco International (SFO) to Denver International (DEN), departs 11:42 AM, arrives 3:30 PM, direct, 2h 48m, $159 per person. Fare as listed by Aviasales: carry-on bag not included (personal item only), checked bag not included, changes not allowed, non-refundable.