| | Amador County | CA | 06005 | | | | | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=AmadorCounty+CA |
| | Calaveras County | CA | 06009 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=CalaverasCounty+CA |
| | Colusa County | CA | 06011 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=ColusaCounty+CA |
| | Glenn County | CA | 06021 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=GlennCounty+CA |
| | Mariposa County | CA | 06043 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=MariposaCounty+CA |
| | Modoc County | CA | 06049 | | | | | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=ModocCounty+CA |
| | Mono County | CA | 06051 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=MonoCounty+CA |
| | Plumas County | CA | 06063 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=PlumasCounty+CA |
| | Sierra County | CA | 06091 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=SierraCounty+CA |
| | Siskiyou County | CA | 06093 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=SiskiyouCounty+CA |