ZIP Code 94099 — South San Francisco, California
📍 ZIP code 94099 is in South San Francisco, San Mateo County, California.
ZIP code 94099 is a PO Box ZIP code assigned by the U.S. Postal Service in South San Francisco, San Mateo County, California. It serves post office boxes at a South San Francisco post office rather than street addresses, which is why the Census Bureau reports no resident population, income or housing figures for it. Mail addressed to 94099 is handled in the Pacific Time Zone and the local area code is 650. The demographic profile of the surrounding community is on the standard delivery ZIP pages for South San Francisco listed below.
ZIP Code 94099 Map
Coordinates: 37.3811°N, 122.3348°W
Why there are no demographics for 94099
The Census Bureau publishes demographics for ZIP Code Tabulation Areas (ZCTAs), which are built from populated census blocks. A PO Box ZIP like 94099 has no delivery territory of its own, so there is no ZCTA and no population, income, housing or education estimate to report. This is normal: San Mateo County and the rest of California have hundreds of PO Box and unique ZIPs of this kind.
For the community around South San Francisco, use the delivery ZIPs that do carry Census data:
How ZIPs and ZCTAs differ is explained on the methodology page.
Nearby Zip Codes
Cities & Places Served
ZIP code 94099 primarily serves South San Francisco in San Mateo County, California.