| Locality | Post Code |
|---|---|
| Anthony, Harper | 67003 |
| Argonia, Harper | 67004 |
| Attica, Harper | 67009 |
| Bluff City, Harper | 67018 |
| Danville, Harper | 67036 |
| Duquoin, Harper | 67058 |
| Freeport, Harper | 67049 |
| Harper, Harper | 67058 |
| Hazelton, Harper | 67061 |
| Waldron, Harper | 67150 |
| Zenda, Harper | 67159 |