West Portal is a principal shopping street for much of southwestern San Francisco, California, and is also considered a neighborhood itself. Named for the western terminus of the Muni tunnel beneath Twin Peaks that opened in 1916, the street (West Portal Avenue) and adjacent district is still dominated by the frequent trundlings of the three Muni Metro lines (K, L and M) that emerge from the subway to run in the street median. The ride in the subway from West Portal to downtown/Union Square is about fifteen minutes.

West Portal lies directly adjacent to several larger San Francisco neighborhoods: the affluent and lushly verdant Forest Hills and St. Francis Woods neighborhoods on the east and south, Parkside (a southern sub-district of the Sunset District) on the north, and at the western end of the Avenue, Lakeshore Village and Merced Manor. The residential areas of the West Portal neighborhood, like several of the adjacent districts, are unusual for San Francisco in that the homes are often detached, albeit with small yards. The frequent fogs help keep the area green in the usually rainless summer months, and on a clear day, a view from the park above the tunnel can be had of the Marin Headlands and the Farallon Islands in the Pacific.

In addition to the streetcar tunnel, West Portal's landmarks include a large movie theater, a library, a school, churches (including the prominent West Portal Lutheran Church and School), restaurants, bars, bookstores, pubs, drugstores, markets and coffeeshops that give the area a distinctly smaller-city, "retro" charm. The West Portal Muni Metro Station is located at the entrance to the Muni tunnel at the northern end of West Portal Avenue.