| Locality | Post Code |
|---|---|
| Bieber, Lassen | 96009 |
| Clear Creek, Lassen | 96137 |
| Doyle, Lassen | 96109 |
| Eagle Lake Resort, Lassen | 96130 |
| Herlong, Lassen | 96113 |
| Janesville, Lassen | 96114 |
| Johnstonville, Lassen | 96130 |
| Lake Almanor, Lassen | 96137 |
| Litchfield, Lassen | 96117 |
| Madeline, Lassen | 96119 |
| Milford, Lassen | 96121 |
| Nubieber, Lassen | 96068 |
| Patton Village, Lassen | 96113 |
| Ravendale, Lassen | 96123 |
| Spaulding, Lassen | 96130 |
| Standish, Lassen | 96128 |
| Susanville, Lassen | 96130 |
| Termo, Lassen | 96132 |
| Wendel, Lassen | 96136 |
| Westwood, Lassen | 96137 |