Flights Seattle → San Francisco — September 14, 2026

One way · Economy · 1 adult · price per person

The cheapest itinerary observed for Monday, September 14, 2026 on the Seattle–San Francisco route: 1 stop itinerary (2 flights) via Denver International (DEN), from Seattle-Tacoma (SEA) to San Francisco International (SFO), first flight Frontier Airlines F93406, departs 4:27 PM, arrives 12:14 AM the next day, total travel time 7h 47m including layovers, flight time 5h 39m (layovers excluded), $176 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 10, 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: Alaska Airlines AS411, from Seattle-Tacoma (SEA) to San Francisco International (SFO), departs 9:25 PM, arrives 11:40 PM, direct, 2h 15m, $292 per person. Fare as listed by Aviasales: carry-on bag included, checked bag not included, changes not allowed, non-refundable.