ZIP Codes in Eureka, CA
Eureka uses 2 ZIP codes, all in Humboldt County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.
All 2 Eureka ZIP codes
| ZIP | Type | County | Population |
|---|---|---|---|
| 95501 | standard | Humboldt | 22,890 |
| 95503 | standard | Humboldt | 25,054 |
Finding a ZIP+4 in Eureka
Knowing which of these 2 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 Eureka street almost always have different ZIP+4 codes even though they share all five leading digits.
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