Flights San Francisco → Denver — September 20, 2026

One way · Economy · 1 adult · price per person

The cheapest itinerary observed for Sunday, September 20, 2026 on the San Francisco–Denver route: 1 stop itinerary (2 flights) via Phoenix Sky Harbor (PHX), from San Francisco International (SFO) to Denver International (DEN), first flight Frontier Airlines F92638, departs 1:10 PM, arrives 11:48 PM, total travel time 9h 38m including layovers, flight time 4h 5m (layovers excluded), $136 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 5, 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 F94310, from San Francisco International (SFO) to Denver International (DEN), departs 9:42 AM, arrives 1:29 PM, direct, 2h 47m, $188 per person. Fare as listed by Aviasales: carry-on bag not included (personal item only), checked bag not included, changes not allowed, non-refundable.