| Nonstop Flights: Austin to/from San Francisco $137 r/t [August-December] â United United has round-trip flights from Austin (AUS) to San Francisco (SFO) for $137, NONSTOP. Flights August to December. Departures on Tuesday, Wednesday, and Saturday. Extended weekends available. Origin/Destination reversible. Click for more details and booking links Nonstop Flights: Austin to/from San Francisco $137 r/t [August-December] â United . | 