South San Francisco, CA ZIP Codes
South San Francisco, California has 2 ZIP codes: for street addresses and for PO boxes.
Mail addressed to South San Francisco covers nearby places too.
Where the 94080 ZIP code reaches
Tap or point to an area to see its ZIP code.Full-size map
94083 has no area on the map: it is a PO box or single-organization ZIP code. Dashed line: South San Francisco city limits.
Map: Census Bureau ZIP Code Tabulation Areas (2020) and place limits (2024).
Check an address in South San Francisco
Street ranges from the Census Bureau, 2026. PO box and organization ZIP codes are not found by street. A new street may be missing: address not found?
South San Francisco PO box and business ZIP codes
| ZIP | Type and post office or station |
|---|---|
| 94080 | street delivery San Bruno |
| 94083 | PO boxes at the Chestnut post office Chestnut |
ZIP codes from nearby towns that reach into South San Francisco
- 94128, mailing town San Francisco, covers 3 percent of South San Francisco
Why your mail may say South San Francisco when you live outside it
A letter addressed to South San Francisco can go to a home outside the city limits, because ZIP areas follow delivery routes, not town lines.
The reverse happens too: parts of South San Francisco use 94128, which mails under a neighboring town's name.
A ZIP code does not set your city, school district or tax. San Mateo County property records show which city you are in.
South San Francisco ZIP code questions
What is the main ZIP code for South San Francisco?
94080, the ZIP code of the main San Bruno post office at 1300 Huntington Ave.
Which South San Francisco ZIP codes are for PO boxes only?
94083. Mail to it goes to boxes at the post office, not to street addresses.
What county is South San Francisco in?
San Mateo County.
ZIP codes for towns near South San Francisco
More towns near South San Francisco: Foster City, Oakland, San Leandro, Redwood City, Hayward, Berkeley, Menlo Park, Castro Valley, Union City.
Sources and last checked
USPS ZIP Locale Detail (October 1, 2026), GeoNames (CC BY 4.0), U.S. Census Bureau, HUD-USPS crosswalk.
Checked October 20, 2026. Sources · How we build our lists · Corrections