| Locality | Post Code |
|---|---|
| Albany, Whiteside | 61230 |
| Brookhaven, Whiteside | 61277 |
| Ceffco, Whiteside | 61230 |
| Clyde, Whiteside | 61270 |
| Coleta, Whiteside | 61081 |
| Deer Grove, Whiteside | 61243 |
| East Clinton, Whiteside | 61252 |
| East Fulton, Whiteside | 61252 |
| Erie, Whiteside | 61250 |
| Fenton, Whiteside | 61251 |
| Fulton, Whiteside | 61252 |
| Galt, Whiteside | 61037 |
| Garden Plain, Whiteside | 61252 |
| Genesee, Whiteside | 61270 |
| Hahnaman, Whiteside | 61283 |
| Leon Corners, Whiteside | 61277 |
| Lyndon, Whiteside | 61261 |
| Malvern, Whiteside | 61270 |
| Morrison, Whiteside | 61270 |
| Portland, Whiteside | 61277 |
| Portland Corners, Whiteside | 61277 |
| Prophetstown, Whiteside | 61277 |
| Rock Falls, Whiteside | 61071 |
| Round Grove, Whiteside | 61270 |
| Sterling, Whiteside | 61081 |
| Tampico, Whiteside | 61283 |