List of California counties

The U.S. state of California is divided into 58 counties. Counties are responsible for local services and law enforcement for areas within their borders that are not within incorporated cites, as well as providing local-level courts.

27 counties were originally created on February 18, 1850; the present number was achieved over time by subdivision of many of the larger counties into smaller ones. The 1850 counties are marked with an asterisk *:

• Alameda
• Alpine
• Amador
• Butte *
• Calaveras *
• Colusa *
• Contra Costa *
• Del Norte
• El Dorado *
• Fresno
• Glenn
• Humboldt
• Imperial
• Inyo
• Kern
• Kings
• Lake
• Lassen
• Los Angeles *
• Madera
• Marin *
• Mariposa *
• Mendocino *
• Merced
• Modoc
• Mono
• Monterey *
• Napa *
• Nevada
• Orange
• Placer
• Plumas
• Riverside
• Sacramento *
• San Benito
• San Bernardino
• San Diego *
• San Francisco *
• San Joaquin *
• San Luis Obispo *
• San Mateo
• Santa Barbara *
• Santa Clara *
• Santa Cruz *
• Shasta *
• Sierra
• Siskiyou
• Solano *
• Sonoma *
• Stanislaus
• Sutter *
• Tehama
• Trinity *
• Tulare
• Tuolumne *
• Ventura
• Yolo *
• Yuba *