| Localité | Code postal |
|---|---|
| Allendorf, Osceola | 51354 |
| Ashton, Osceola | 51232 |
| Cloverdale, Osceola | 51249 |
| Harris, Osceola | 51345 |
| May, Osceola | 51354 |
| May City, Osceola | 51354 |
| Melvin, Osceola | 51350 |
| Ocheyedan, Osceola | 51354 |
| Sheldon, Osceola | 51201 |
| Sibley, Osceola | 51249 |