Which Terminal is Southwest Airlines at SFO San Francisco International Airport’s (SFO) Terminal 1 is home to Southwest Airlines. One of SFO’s three main terminals, Terminal 1 (sometimes called the Harvey Milk Terminal 1), serves both domestic and some international flights. Travelers using Southwest Airlines will find a convenient and efficient experience as all of their ticketing, check-in, and baggage claim facilities are housed within this terminal. Before your travel, be careful to check Southwest’s updates or the airport’s website for any potential changes to terminal assignments.Â