| Nonstop Flights: Austin to/from San Francisco $97 r/t [September-October] â United United has round-trip flights from Austin (AUS) to San Francisco (SFO) for $97, NONSTOP. Flights September to October. No Monday departures. Weekends available. Origin/Destination reversible. Fare has bag fees. Alaska Airlines has flights for about +$30 more with bags and seat selection included in the price. Click for more details and booking links Nonstop Flights: Austin to/from San Francisco $97 r/t [September-October] â United . | 