| Locality | Postal Code |
|---|---|
| Alexander Springs, Mifflin | 17004 |
| Alfarata, Mifflin | 17841 |
| Allensville, Mifflin | 17002 |
| Anderson, Mifflin | 17029 |
| Atkinsons Mills, Mifflin | 17051 |
| Bannerville, Mifflin | 17841 |
| Barrville, Mifflin | 17084 |
| Belleville, Mifflin | 17004 |
| Belltown, Mifflin | 17841 |
| Bratton, Mifflin | 17044 |
| Burnham, Mifflin | 17009 |
| Colonial Hill, Mifflin | 17044 |
| Crossgrove, Mifflin | 17841 |
| Decatur, Mifflin | 17841 |
| Gardenview, Mifflin | 17084 |
| Granville, Mifflin | 17029 |
| Hawstone, Mifflin | 17044 |
| Horningford, Mifflin | 17044 |
| Juniata Terr, Mifflin | 17044 |
| Klondyke, Mifflin | 17044 |
| Lewistown, Mifflin | 17044 |
| Little Kansas, Mifflin | 17051 |
| Locke Mills, Mifflin | 17063 |
| Longfellow, Mifflin | 17044 |
| Maitland, Mifflin | 17044 |
| Mattawana, Mifflin | 17054 |