| Locality | Post Code |
|---|---|
| Adco, Grant | 98851 |
| Adrian, Grant | 98851 |
| Beverly, Grant | 99321 |
| Coulee City, Grant | 99115 |
| Desert Aire, Grant | 99349 |
| Electric City, Grant | 99123 |
| Ephrata, Grant | 98823 |
| George, Grant | 98824 |
| Grand Coulee, Grant | 99133 |
| Hartline, Grant | 99135 |
| Krupp, Grant | 98832 |
| Lakeview Park, Grant | 98851 |
| Mae, Grant | 98837 |
| Marlin, Grant | 98832 |
| Mattawa, Grant | 99349 |
| Moses Lake, Grant | 98837 |
| Quincy, Grant | 98848 |
| Raugust, Grant | 98837 |
| Royal City, Grant | 99357 |
| Ruff, Grant | 98832 |
| Schawana, Grant | 99321 |
| Soap Lake, Grant | 98851 |
| Stratford, Grant | 98853 |
| Trinidad, Grant | 98848 |
| Warden, Grant | 98857 |
| Wheeler, Grant | 98837 |