ZIP Codes in Waterloo, IA
Waterloo uses 3 ZIP codes, all in Black Hawk County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.
All 3 Waterloo ZIP codes
| ZIP | Type | County | Population |
|---|---|---|---|
| 50701 | standard | Black Hawk | 30,232 |
| 50702 | standard | Black Hawk | 20,882 |
| 50703 | standard | Black Hawk | 17,952 |
Finding a ZIP+4 in Waterloo
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 Waterloo 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 Waterloo addresses and download it complete.