| Regional Center | Counties |
| Alta California Regional Center | Alpine, Colusa, El Dorado, Nevada, Placer, Sacramento, Sierra, Sutter, Yuba, and Yolo |
| Central Valley Regional Center | Fresno, Kings, Madera, Mariposa, Merced, and Tulare |
| Eastern Lost Angeles Regional Center | Los Angeles (Alhambra, East Los Angeles, Northeast, Whittier) |
| Far Northern Regional Center | Butte, Glenn, Lassen, Modoc, Plumas, Shasta, Siskiyou, Tehama, Trinity |
| Frank D. Lanterman Regional Center | Los Angeles (Central, Glendale, Hollywood-Wilshire, Pasadena) |
| Golden Gate Regional Center | Marin, San Mateo, and San Francisco |
| Harbor Regional Center | Los Angeles (Bellflower, Harbor, Long Beach, and Torrance) |
| Inland Regional Center | Riverside and San Bernardino |
| Kern Regional Center | Inyo, Kern, and Mono |
| North Bay Regional Center | Napa, Solano, and Sonoma |
| North Los Angeles County Regional Center | Los Angeles (East Valley, San Fernando, and West Valley) |
| Redwood Coast Regional Center | Del Norte, Humboldt, Lake, and Mendocino |
| Regional Center of East Bay | Alameda and Contra Costa |
| Regional Center of Orange County | Orange County |
| San Andreas Regional Center | Monterey, San Benito, Santa Clara, and Santa Cruz |
| San Diego Regional Center | Imperial and San Diego |
| San Gabriel/Pomona Regional Center | Los Angeles (El Monte, Glendora, Monrovia, and Pomona) |
| South Central Los Angeles Regional Center | Los Angeles (Compton, San Antonio, South, Southeast, and Southwest) |
| Tri-Counties Regional Center | San Luis Obispo, Santa Barbara, and Ventura |
| Valley Mountain Regional Center | Amador, Calaveras, San Joaquin, Stanislaus, and Tuolumne |
| Westside Regional Center | Los Angeles (Inglewood and Santa Monica–West)
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