BEST WAY DOWNTOWN:
The airport is 14 miles (22 km) south of downtown San Francisco. There are ground transportation counters in the baggage claim areas of all terminals.
The airport's website has maps and ground transportation information. The Quickaid website also has information on ground transportation.
There are plenty of taxis available. Go to the dispatchers area outside the arrivals terminal and tell them your destination. You will them be directed to a taxi. The fare is metered, and the fare to the downtown area will be $26 to $32 depending on the traffic. The ride should take about 25 minutes, and up to 40 minutes during the rush hours.
A bus called the SFO Airporter leaves from the terminal, in front of the lower level baggage claim area. There are three different routes that the Airporters serve. Buses leave every 20 to 30 minutes from 5 A.M. to midnight, and it will take 25 to 40 minutes for the trip downtown. Tickets ($10 one-way, $18 round-trip, $14 round-trip if return is on the same day) are sold at the desk in the baggage claim area, by the light blue pillar. The SFO Airporter bus stops at major Union Square Hotels such as the Westin St. Francis, Grand Hyatt, Sheraton Plaza, Nikko, Marriott, and the San Francisco Hilton.
Super Shuttle (800-BLUE-VAN) goes to Nob Hill hotels such as the Mark Hopkins, Ritz-Carlton, Mark Twain, Holiday Inn-Financial District, Park Hyatt, Moscone Center, etc. The Wharf Airporter serves the hotels along the waterfront, wharf, and Ghiradelli Square. Check with the transportation counter or the Airporter Desk to find out which route serves your hotel. If your hotel is not on one of these routes, simply take the bus to an area close to your hotel, then take a taxi to your final destination. This is a very good and cost effective way to get downtown.
to get to the East Bay or Marin County, try Davis Airporter at 503-756-6115 or Marin Door-to-Door at 800-540-4815 (in San Francisco call 415-457-2717).
If you are traveling in a group of four or five, it is cost effective to rent a limousine for the ride downtown. Go to the limousine counter near baggage claim. The price is around $60, so $15 each for a group of four is not a bad price to ride in comfort.
All the major rental car companies are represented at the airport.
World Airport Information
Adapted from How to Get Out of the Airport