| Locality | Post Code |
|---|---|
| Ada, Hardin | 45810 |
| Alger, Hardin | 45812 |
| Dola, Hardin | 45835 |
| Dunkirk, Hardin | 45836 |
| Forest, Hardin | 45843 |
| Hepburn, Hardin | 43326 |
| Kenton, Hardin | 43326 |
| McGuffey, Hardin | 45859 |
| Mount Victory, Hardin | 43340 |
| Ridgeway, Hardin | 43345 |
| Roundhead, Hardin | 43346 |