Post Offices List in Mason County, Michigan:
| Branch Post Office | 11952 W Us Highway 10, Branch, MI 49402 |
| Custer Post Office | 9 S Madison Ave, Custer, MI 49405 |
| Fountain Post Office | 5016 N Cleveland St, Fountain, MI 49410 |
| Free Soil Post Office | 2650 E Michigan St, Free Soil, MI 49411 |
| Ludington Post Office | 201 E Ludington Ave, Ludington, MI 49431 |
| Scottville Post Office | 202 S Main St, Scottville, MI 49454 |
| Walhalla Post Office | 6635 E Us Highway 10, Walhalla, MI 49458 |