| ZIP Code | ZIP Code Place Name | County | ZIP Code Type |
|---|---|---|---|
| 45310 | Burkettsville | Mercer County | PO Box |
| 45822 | Celina | Mercer County | Standard |
| 45826 | Chickasaw | Mercer County | PO Box |
| 45828 | Coldwater | Mercer County | Standard |
| 45845 | Fort Loramie | Shelby County | Standard |
| 45846 | Fort Recovery | Mercer County | Standard |
| 45860 | Maria Stein | Mercer County | Standard |
| 45862 | Mendon | Mercer County | Standard |
| 45866 | Montezuma | Mercer County | PO Box |
| 45869 | New Bremen | Auglaize County | Standard |
| 45882 | Rockford | Mercer County | Standard |
| 45883 | Saint Henry | Mercer County | Standard |
| 45887 | Spencerville | Allen County | Standard |
| 45894 | Venedocia | Van Wert County | Standard |
| 45898 | Willshire | Van Wert County | Standard |