Post Offices List in Alexander County, Illinois:
| Cairo Post Office | 1500 Washington Ave, Cairo, IL 62914 |
| MC Clure Post Office | 37914 Grapevine Trl, Mc Clure, IL 62957 |
| Olive Branch Post Office | 22475 Railroad St, Olive Branch, IL 62969 |
| Tamms Post Office | 250 Front St, Tamms, IL 62988 |
| Thebes Post Office | 815 Poplar St, Thebes, IL 62990 |