ZIP Codes in Florissant, MO
Florissant uses 3 ZIP codes, all in St. Louis County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.
All 3 Florissant ZIP codes
| ZIP | Type | County | Population |
|---|---|---|---|
| 63031 | standard | St. Louis | 50,196 |
| 63033 | standard | St. Louis | 43,056 |
| 63034 | standard | St. Louis | 18,908 |
Finding a ZIP+4 in Florissant
Knowing which of these 3 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 Florissant street almost always have different ZIP+4 codes even though they share all five leading digits.
Appending ZIP+4 to a mailing list?
Upload a CSV of Florissant addresses and download it complete.