Post Offices List in Custer County, South Dakota:
| Buffalo Gap Post Office | 200 N Walnut St, Buffalo Gap, SD 57722 |
| Custer Post Office | 643 Mount Rushmore Rd, Custer, SD 57730 |
| Fairburn Post Office | 120 Oak St, Fairburn, SD 57738 |
| Hermosa Post Office | 208 Main St, Hermosa, SD 57744 |
| Pringle Post Office | 369 Main St, Pringle, SD 57773 |