Airport Express provides transfer service between San Francisco, Oakland, and Sonoma County since 1980. The pickup and drop-off services are available in the largest communities of Sonoma as Petaluma, Rohnert Park, and Santa Rosa. The first bus departing from the STS Airport runs at 02:45 and the last one at 21:45. The first bus leaving from the Park & Ride Santa Rosa runs at 03:00 and the last one at 22:00. The first bus going from the Doubletree Hotel Rohnert Park runs at 03:15 and the last one at 22:15. The first bus departing from the Petaluma Fairgrounds Terminal runs at 03:30 and the last one at 22:30. The first bus leaving from the SFO San Francisco runs at 05:30 and the last one at 00:30. The first bus arrives at the SFO San Francisco at 05:00 and the last one at 00:00. The one-way fare to or from Sonoma County is $36 for the adults, $34 for disabled, military workers, students, and concessions, and is free of charge for children under 12.
Santa Rosa Airport shuttles are providing transfers to and from the airport. The prices vary depending on the distance covered. Shuttle service providers are aka Blue Van, GO Airport Shuttle, SuperShuttle, Caramel Car, etc.