| ZIP Code | ZIP Code Place Name | County | ZIP Code Type |
|---|---|---|---|
| 52037 | Delmar | Clinton County | Standard |
| 52060 | Maquoketa | Jackson County | Standard |
| 52064 | Miles | Jackson County | Standard |
| 52069 | Preston | Jackson County | Standard |
| 52070 | Sabula | Jackson County | Standard |
| 52207 | Baldwin | Jackson County | Standard |
| 52254 | Lost Nation | Clinton County | Standard |
| 52323 | Oxford Junction | Jones County | Standard |
| 52701 | Andover | Clinton County | PO Box |
| 52727 | Bryant | Clinton County | Standard |
| 52729 | Calamus | Clinton County | Standard |
| 52730 | Camanche | Clinton County | Standard |
| 52731 | Charlotte | Clinton County | Standard |
| 52732 | Clinton | Clinton County | Standard |
| 52733 | Clinton | Clinton County | PO Box |
| 52734 | Clinton | Clinton County | Unique |
| 52736 | Clinton | Clinton County | Unique |
| 52742 | De Witt | Clinton County | Standard |
| 52750 | Goose Lake | Clinton County | Standard |
| 52751 | Grand Mound | Clinton County | Standard |
| 52757 | Low Moor | Clinton County | PO Box |
| 52771 | Teeds Grove | Clinton County | Standard |
| 52774 | Welton | Clinton County | PO Box |
| 52777 | Wheatland | Clinton County | Standard |