| Zip Code | City | Population ↓ |
|---|---|---|
| 96130 | Susanville | 20,173 |
| 96114 | Janesville | 2,959 |
| 96137 | Westwood | 2,923 |
| 96113 | Herlong | 2,039 |
| 96056 | Mcarthur | 1,584 |
| 96109 | Doyle | 1,299 |
| 96128 | Standish | 656 |
| 96006 | Adin | 512 |
| 96009 | Bieber | 307 |
| 96117 | Litchfield | 261 |
| 96121 | Milford | 217 |
| 96068 | Nubieber | 94 |
| 96123 | Ravendale | 45 |
| 96136 | Wendel | 27 |
| 96132 | Termo | 21 |
| 96119 | Madeline | 6 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 16 ZCTAs in Lassen County, California (US Census).