San Francisco, CA

ZIP code 94104 is assigned to San Francisco, CA, and falls within City and County of San Francisco County. Like every US postal code, it began as a mail-routing device rather than a geographic boundary — the US Postal Service groups delivery routes under a single code so carriers and sorting equipment can process mail efficiently. Today it also serves as a practical shorthand for the area itself: roughly 478 people live inside it.

At 6,128 residents per square mile spread over 0.078 square miles, 94104 reads as a densely built-up area. It is a sparsely populated postal code, and density shapes almost everything else on this page — how people get to work, whether they own or rent, and what housing costs.

Household earnings run below the national median. At $49,896, 94104 sits in the lower half, ahead of 16% of them. The US median for comparison is $70,109. Bear in mind that median income describes the midpoint household, not the average — it is not pulled upward by a handful of very high earners the way a mean would be.

Housing in 94104 costs far above the national median. A typical home is valued at $1,992,600 against a US median of $207,500, and median gross rent runs $783 a month. This is firmly renter territory — 69.2% of occupied homes are rented, a pattern typical of city centres, student areas and neighbourhoods with a lot of apartment stock.

The building stock is dominated by larger apartment buildings of twenty units or more, which account for 70.7% of housing units here. The median construction year is 1938, making the housing here largely pre-war.

The population skews considerably older than the national median, with a median age of 54.2 against 42 nationally. Households average just 1.82 people, and 36.9% consist of one person living alone — a signature of areas with a lot of studio and one-bedroom stock.

Getting to work takes 33.6 minutes on average one way. The dominant mode is walked at 48.8% of workers, while 42.4% take public transit, 48.8% walk. Commute patterns are one of the better proxies for how a place actually functions day to day.

Beyond addressing mail, 94104 does a lot of quiet administrative work. Retailers use it to calculate shipping and sales tax at checkout. Insurers use it to set premiums, since risk profiles vary geographically. Employers and marketers use it to define service areas. Government agencies use it to route benefits and organise reporting. If you have ever been asked for a postal code by a form that clearly does not intend to send you anything, this is why.

For anyone weighing a move, 94104 offers a compact profile of San Francisco: 478 residents, a median household income of $49,896, 48.2% of adults holding a bachelor's degree or higher, and an unemployment rate of 36.5%. A handful of figures like these answer more relocation questions than most neighbourhood guides do.

One caution worth repeating: a postal code is not a neighbourhood. 94104 may cover parts of several distinct areas, and a single neighbourhood in San Francisco may be split across more than one code. Boundaries also shift as USPS adjusts delivery routes. Treat the figures here as describing a delivery area, which is what they actually measure.