About two thirds of the active fleet is assigned to run on the SF MUNI F-Line on a regular basis. The F-Line's rolling stock provides a flashback to the past while its routing provides practical public transit service. The F-Line operates exclusively historic streetcars consisting of primarily restored St. Louis Car Co. PCC's and Peter Witt "Milan" trams (August 2006). The antique streetcars (odds and ends) make occasional appearances on the F-Line.

Many of the historic streetcars that MUNI currently owns never did operate in San Francisco till they were brought into the historic fleet in San Francisco. As a result, there is no standard paint scheme for the historic fleet, rather the paint schemes that are on the various cars either represent the city that the streetcar originally came from or in the case of most PCC streetcars, represents a city that use to operate the famous PCC streetcars. Most if not all of the historic fleet is capable of running on any MUNI Metro tracks, except for the Market Street "Subway".