Terminal layout & organization
San Francisco International Airport (SFO) is organized as a ring of terminals and concourses, with four main terminal buildings serving seven concourses. Domestic flights primarily use Harvey Milk Terminal 1, Terminal 2, and Terminal 3, while international flights center on the International Terminal (split into International Terminal A and International Terminal G). Airline operations are clustered: Terminal 3 is largely United (E and F gates), Harvey Milk Terminal 1 hosts several domestic carriers (B and C gates), and Terminal 2 is home to Delta and select partners (C and D gates). For international departures, check whether you’re leaving from International Terminal A or International Terminal G—they are distinct concourses with different airlines and lounge options.
You may also see older or alternate naming used by some sources; at SFO the official passenger terminals are the four above—so treat names like Dianne Feinstein International Terminal and Tom Bradley International Terminal as references you should verify against your boarding pass, airline app, and SFO’s terminal maps.
Navigation between terminals
Your main tool is AirTrain, SFO’s free 24/7 people mover that connects all terminals, parking, and the rental car center. Trains typically arrive about every 4 minutes; most terminal-to-terminal rides take roughly 5–10 minutes depending on direction and stops. Walking can be quick in a few places: there are connectors between Terminal 2 and Terminal 3 landside, and several post-security links (including Terminal 3 to International Terminal G). Because there isn’t a simple full ring walkway, use AirTrain if you’re not sure you can stay airside. Follow overhead signs for “AirTrain”, “International”, and the gate letters (A–G); when in doubt, confirm your gate letter first, then navigate to that concourse.
Traveler-specific tips
- Families: All terminals are stroller-friendly with elevators and wide corridors. Look for family restrooms and nursing rooms near restrooms in major concourses; if you need a quiet reset, the International Terminal’s larger public areas can feel less cramped than peak domestic holdrooms.
- Business travelers: Concentrate lounge-hopping in the International Terminal (the greatest lounge density) and Terminal 3 (United Club options). Note: the Amex Centurion Lounge in Terminal 3 is closed until 2027, with a temporary Centurion space operating in Terminal 2.
- Accessibility: SFO is fully accessible with ramps, elevators, and accessible restrooms. Request wheelchair assistance through your airline, and use AirTrain for step-free terminal transfers.
- Budget: Bring an empty bottle—water bottle filling stations are common across terminals—and use abundant charging outlets around gate seating and food courts (scan under counters and along seating walls).
Practical information
Free Wi-Fi is available throughout SFO and is generally reliable for messaging and work on typical days; if it slows, move closer to a gate area or main hall. Power outlets are easiest to find in newer seating clusters in Harvey Milk Terminal 1, Terminal 2, and Terminal 3, plus throughout the International Terminal check-in and gate areas. For help, use airline counters and airport information points in the main halls—especially the International Terminal central area, which also provides access to BART and key services. Before you leave security, double-check any closures or detours in Terminal 3 related to the Centurion Lounge project and follow posted wayfinding signs for alternate routes.