| Locality | Post Code |
|---|---|
| Carrollton, Carroll | 21157 |
| Detour, Carroll | 21757 |
| Eldersburg, Carroll | 21784 |
| Finksburg, Carroll | 21048 |
| Gaither, Carroll | 21784 |
| Greenmount, Carroll | 21074 |
| Hampstead, Carroll | 21074 |
| Henryton, Carroll | 21104 |
| Keymar, Carroll | 21757 |
| Lineboro, Carroll | 21102 |
| Linwood, Carroll | 21791 |
| Manchester, Carroll | 21102 |
| Middleburg, Carroll | 21757 |
| Millers, Carroll | 21102 |
| New Windsor, Carroll | 21776 |
| Patapsco, Carroll | 21048 |
| Sykesville, Carroll | 21784 |
| Taneytown, Carroll | 21787 |
| Union Bridge, Carroll | 21791 |
| Westminster, Carroll | 21157, 21158 |
| Woodstock, Carroll | 21104 |