ZIP Codes in Walnut Creek, CA
Walnut Creek uses 4 ZIP codes, all in Contra Costa County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.
All 4 Walnut Creek ZIP codes
| ZIP | Type | County | Population |
|---|---|---|---|
| 94595 | standard | Contra Costa | 16,988 |
| 94596 | standard | Contra Costa | 23,417 |
| 94597 | standard | Contra Costa | 23,129 |
| 94598 | standard | Contra Costa | 27,206 |
Finding a ZIP+4 in Walnut Creek
Knowing which of these 4 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 Walnut Creek street almost always have different ZIP+4 codes even though they share all five leading digits.
Appending ZIP+4 to a mailing list?
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