The San Francisco Municipal Railway (SF Muni or Muni ) is the primary public transit system within San Francisco, California. It operates a system of bus routes (including trolleybuses), the Muni Metro light rail system, three historic cable car lines, and two historic streetcar lines. Previously an independent agency, the San Francisco Municipal Railway merged with two other agencies in 1999 to become the San Francisco Municipal Transportation Agency (SFMTA). In 2018, Muni served with an operating budget of about $1.2 billion. Muni is the seventh highest-ridership transit system in the United States, with rides in , and the second highest in California after the Los Angeles County Metropolitan Transportation Authority.

Operations

thumb|right|A cable car being turned around at the end of the line, August 1964

Most bus lines are scheduled to operate every five to fifteen minutes during peak hours, every five to twenty minutes middays, about every ten to twenty minutes from 9&nbsp;pm to midnight, and roughly every half-hour for the late night "owl" routes. On weekends, most Muni bus lines are scheduled to run every ten to twenty minutes. However, complaints of unreliability, especially on less-often-served lines and older (pre-battery backup) trolleybus lines, are a system-wide problem. Muni has had some difficulty meeting a stated goal of 85% voter-demanded on-time service.<!--created separate ref since didn't match other given ref-->

All Muni lines run inside San Francisco city limits, with the exception of several lines serving locations in the northern part of neighboring Daly City, and the 76X Marin Headlands Express line to the Marin Headlands area on weekends and major holidays. Most intercity connections are provided by BART and Caltrain heavy rail, AC Transit buses at the Salesforce Transit Center, and Golden Gate Transit and SamTrans downtown.

Bus and cable car stops throughout the city vary from Metro stations with raised platforms in the subway and at the more heavily used surface stops, to small shelters to signposts to simply a yellow stripe on a utility pole or on the road surface. 70% of stops are spaced closer than recommended range of apart.

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The system is popularly known as "Muni", a shortening of the "Municipal" in "San Francisco Municipal Railway" (and not an acronym). Muni's logo is a stylized, trademarked "worm" version of the word muni. This logo was designed by San Francisco-based graphic designer Walter Landor in the mid-1970s.

Announcements

To cater to the large Hispanic and Latino American and Asian American populations in San Francisco, bus announcements are in four languages: English, Spanish, Cantonese and Tagalog.

Route names

Bus and trolleybus lines are identified by a number and a route name that typically incorporates the street on which the route operates its longest segment, though it is occasionally a destination or landmark. For example, the 1-California line runs the majority of its route along California Street. Rail lines have letters as well as a name designation (J-Church, K-Ingleside, L-Taraval, M-Ocean View, N-Judah, T-Third), and the three cable car lines are typically referred to by name only (Powell-Mason, Powell-Hyde and California).

Fares

Except for cable cars, cash fares are $3.00 for adults; $1.50 for seniors over 65, people with disabilities, and Medicare card holders; and free for low- and moderate-income seniors, youth aged 18 and under, and people with disabilities residing in San Francisco. Clipper card and MuniMobile fares are $2.85 for adults and $1.40 for seniors and people with disabilities. Proof-of-payment, which fare inspectors may demand at any time, is either a Clipper card, MuniMobile, Muni Passport, or paper transfer. One fare entitles a rider to unlimited vehicle transfers for the next 120 minutes.