| | Alameda County | CA | 06001 | Oakland-Fremont-Berkeley,
CA 36084 | San
Francisco-Oakland-Fremont,
CA 41860 | San Jose-San
Francisco-Oakland, CA 488 | Central | in metro of > 1m | nonspecialized | https://maps.google.com/?q=AlamedaCounty+CA |
| | Alpine County | CA | 06003 | | Gardnerville Ranchos, NV 23820 | Reno-Carson
City-Gardnerville
Ranchos, NV-CA 456 | Outlying | not in metro; pop <
5k; metro-adjacent | recreation | https://maps.google.com/?q=AlpineCounty+CA |
| | Amador County | CA | 06005 | | | | | not in metro; pop > 5k
< 20k; metro-adjacent | federal/state
government-dependent | https://maps.google.com/?q=AmadorCounty+CA |
| | Butte County | CA | 06007 | | Chico, CA 17020 | | Central | in metro of < 250k | nonspecialized | https://maps.google.com/?q=ButteCounty+CA |
| | Calaveras County | CA | 06009 | | | | | not in metro; pop > 5k
< 20k; metro-adjacent | recreation | https://maps.google.com/?q=CalaverasCounty+CA |
| | Colusa County | CA | 06011 | | | | | not in metro; pop > 5k
< 20k; metro-adjacent | farm-dependent | https://maps.google.com/?q=ColusaCounty+CA |
| | Contra Costa County | CA | 06013 | Oakland-Fremont-Berkeley,
CA 36084 | San
Francisco-Oakland-Fremont,
CA 41860 | San Jose-San
Francisco-Oakland, CA 488 | Outlying | in metro of > 1m | nonspecialized | https://maps.google.com/?q=ContraCostaCounty+CA |
| | Del Norte County | CA | 06015 | | Crescent City, CA 18860 | Brookings-Crescent City,
OR-CA 152 | Central | not in metro; pop > 5K
< 20k;
non-metro-adjacent | federal/state
government-dependent | https://maps.google.com/?q=DelNorteCounty+CA |
| | El Dorado County | CA | 06017 | | Sacramento-Roseville-Folsom,
CA 40900 | Sacramento-Roseville, CA 472 | Central | in metro of > 1m | recreation | https://maps.google.com/?q=ElDoradoCounty+CA |
| | Fresno County | CA | 06019 | | Fresno, CA 23420 | Fresno-Hanford-Corcoran,
CA 260 | Central | in metro of > 1m | nonspecialized | https://maps.google.com/?q=FresnoCounty+CA |