ZIP Codes in Arnold, MO
Arnold uses 1 ZIP code, all in Jefferson County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.
All 1 Arnold ZIP codes
| ZIP | Type | County | Population |
|---|---|---|---|
| 63010 | standard | Jefferson | 34,478 |
Finding a ZIP+4 in Arnold
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 Arnold 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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