| Locality | Post Code |
|---|---|
| Alabaster, Iosco | 48763 |
| Au Sable, Iosco | 48750 |
| East Tawas, Iosco | 48730 |
| Hale, Iosco | 48739 |
| Long Lake, Iosco | 48743 |
| National City, Iosco | 48748 |
| Oscoda, Iosco | 48750 |
| South Branch, Iosco | 48761 |
| Tawas City, Iosco | 48763 |
| Turner, Iosco | 48765 |
| Whittemore, Iosco | 48770 |