| Locality | Post Code |
|---|---|
| Brooklyn, Poweshiek | 52211 |
| Chelsea, Poweshiek | 52215 |
| Deep River, Poweshiek | 52222 |
| Ewart, Poweshiek | 50171 |
| Gibson, Poweshiek | 50104 |
| Grinnell, Poweshiek | 50112 |
| Guernsey, Poweshiek | 52221 |
| Hartwick, Poweshiek | 52232 |
| Holiday Lake, Poweshiek | 52211 |
| Malcom, Poweshiek | 50157 |
| Montezuma, Poweshiek | 50171 |
| Newburg, Poweshiek | 50112 |
| Oakland Acres, Poweshiek | 50112 |
| Searsboro, Poweshiek | 50242 |
| Sheridan, Poweshiek | 50157 |
| Victor, Poweshiek | 52347 |