| Locality | Post Code |
|---|---|
| Specktown, Dauphin | 17048 |
| Spring Glen, Dauphin | 17978 |
| Steelton, Dauphin | 17113 |
| Stoverdale, Dauphin | 17036 |
| Swatara, Dauphin | 17111 |
| Swatara Station, Dauphin | 17033 |
| Tower City, Dauphin | 17980 |
| Union Deposit, Dauphin | 17033 |
| Upper Paxton, Dauphin | 17061 |
| Waltonville, Dauphin | 17036 |
| Water Gap, Dauphin | 17018 |
| Waynesville, Dauphin | 17032 |
| West End, Dauphin | 17102 |
| West Hanover, Dauphin | 17112 |
| Wiconisco, Dauphin | 17097 |
| Williams, Dauphin | 17098 |
| Williamstown, Dauphin | 17098 |