| Localité | Code postal |
|---|---|
| Attila, Williamson | 62974 |
| Blairsville, Williamson | 62918 |
| Cambria, Williamson | 62915 |
| Carterville, Williamson | 62918 |
| Colp, Williamson | 62921 |
| Crainville, Williamson | 62918 |
| Creal Springs, Williamson | 62922 |
| Dewmaine, Williamson | 62918 |
| Egyptian Hills, Williamson | 62922 |
| Egyptian Shores, Williamson | 62922 |
| Energy, Williamson | 62933 |
| Ferges, Williamson | 62951 |
| Fergestown, Williamson | 62951 |
| Freeman Spur, Williamson | 62841 |
| Hafer, Williamson | 62918 |
| Herrin, Williamson | 62948 |
| Hurst, Williamson | 62949 |
| Johnston City, Williamson | 62951 |
| Lake Crest, Williamson | 62922 |
| Marion, Williamson | 62959 |
| New Camp, Williamson | 62921 |
| Old Camp, Williamson | 62921 |
| Paineville, Williamson | 62948 |
| Pittsburg, Williamson | 62974 |
| Shakerag, Williamson | 62951 |
| Spillertown, Williamson | 62959 |