zip4lookup

ZIP Codes in Portola Valley, CA

Portola Valley uses 1 ZIP code, all in San Mateo County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.

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All 1 Portola Valley ZIP codes

ZIPTypeCountyPopulation
94028 standard San Mateo 6,531

Finding a ZIP+4 in Portola Valley

Knowing which of these 1 ZIP codes covers an address only gets you partway. The four-digit extension identifies the specific delivery point — typically one side of one block. Two houses facing each other on the same Portola Valley street almost always have different ZIP+4 codes even though they share all five leading digits.

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