| Locality | Post Code |
|---|---|
| Alton, Sioux | 51003 |
| Boyden, Sioux | 51234 |
| Carmel, Sioux | 51247 |
| Carnes, Sioux | 51003 |
| Chatsworth, Sioux | 51011 |
| Granville, Sioux | 51022 |
| Hawarden, Sioux | 51023 |
| Hospers, Sioux | 51238 |
| Hull, Sioux | 51239 |
| Ireton, Sioux | 51027 |
| Lebanon, Sioux | 51250 |
| Matlock, Sioux | 51244 |
| Maurice, Sioux | 51036 |
| McNally, Sioux | 51027 |
| Middleburg, Sioux | 51041 |
| Newkirk, Sioux | 51238 |
| Orange City, Sioux | 51041 |
| Perkins, Sioux | 51239 |
| Rock Valley, Sioux | 51247 |
| Sheldon, Sioux | 51201 |
| Sioux Center, Sioux | 51250 |