The current number of counties was achieved over time by subdivision of many of the larger counties into smaller ones. The links in the column FIPS County Code are to the Census Bureau Info page for that county. The map at the right hand side also shows the FIPS codes for all the counties (on one map for easy reference).
County
|
FIPS Code
2 |
County seat
3 |
Established
3 |
Origin
|
Etymolgy
|
Population
3 |
Area
3 |
Map
|
| Alameda County |
001 |
Oakland |
1853 |
Parts of Contra Costa County and Santa Clara County. |
Spanish word meaning a "cottonwood grove". |
&0000000001443741.0000001,443,741 |
&0000000000000738.000000738 mi²
(1,911 km²) |
 |
| Alpine County |
003 |
Markleeville |
1864 |
Parts of Amador County, El Dorado County, Calaveras County, Mono County and Tuolumne County. |
English word meaning "of, pertaining to, or connected with, the Alps". |
&0000000000001208.0000001,208 |
&0000000000000739.000000739 sq mi
(&0000000000001914.0000001,914 km²) |
 |
| Amador County |
005 |
Jackson |
1854 |
Part of Calaveras County. |
Jose Maria Amador (1794-1883), a soldier, rancher and miner. In Spanish, the word amador means "lover". |
&0000000000035100.00000035,100 |
&0000000000000593.000000593 sq mi
(&0000000000001536.0000001,536 km²) |
 |
| Butte County |
007 |
Oroville |
1850 |
One of the twenty-seven original counties. |
From the Sutter Buttes, which lay within the county's borders at the time of its creation. |
&0000000000203171.000000203,171 |
&0000000000001640.0000001,640 sq mi
(&0000000000004248.0000004,248 km²) |
 |
| Calaveras County |
009 |
San Andreas |
1850 |
One of the twenty-seven original counties. |
From the Calaveras River which in turn is named for the spanish word for skulls |
&0000000000040554.00000040,554 |
&0000000000001020.0000001,020 sq mi
(&0000000000002642.0000002,642 km²) |
 |
| Colusa County |
011 |
Colusa |
1850 |
One of the twenty-seven original counties. |
From two Mexican land grants; Coluses (1844) and Colus (1845). |
&0000000000018804.00000018,804 |
&0000000000001151.0000001,151 sq mi
(&0000000000002981.0000002,981 km²) |
 |
| Contra Costa County |
013 |
Martinez |
1850 |
One of the twenty-seven original counties. |
Spanish for opposite coast, because Contra Costa County is across San Francisco Bay from San Francisco. |
&0000000000948816.000000948,816 |
&0000000000000720.000000720 sq mi
(&0000000000001865.0000001,865 km²) |
 |
| Del Norte County |
015 |
Crescent City |
1857 |
Part of Klamath County. |
Spanish for Northern, because Del Norte County is the northwesternmost county in the state. |
&0000000000027507.00000027,507 |
&0000000000001008.0000001,008 sq mi
(&0000000000002611.0000002,611 km²) |
 |
| El Dorado County |
017 |
Placerville |
1850 |
One of the twenty-seven original counties. |
From the mythical El Dorado, The Gilded One, in relation to El Dorado County's importance in the California Gold Rush. |
&0000000000156299.000000156,299 |
&0000000000001712.0000001,712 sq mi
(&0000000000004434.0000004,434 km²) |
 |
| Fresno County |
019 |
Fresno |
1856 |
Parts of Mariposa County, Merced County and Tulare County. |
From Fresno Creek. In Spanish, Fresno means "ash tree". |
&0000000000799407.000000799,407 |
&0000000000005963.0000005,963 sq mi
(&0000000000015444.00000015,444 km²) |
 |
| Glenn County |
021 |
Willows |
1891 |
Part of Colusa County. |
Named for Dr. Hugh J. Glenn (1824-1883), a California businessman and politician. |
&0000000000026453.00000026,453 |
&0000000000001315.0000001,315 sq mi
(&0000000000003406.0000003,406 km²) |
 |
| Humboldt County |
023 |
Eureka |
1853 |
Part of Trinity County. |
From Humboldt Bay, named for Baron Alexander von Humboldt (1769-1859), a Prussian naturalist and explorer. |
&0000000000126518.000000126,518 |
&0000000000003573.0000003,573 sq mi
(&0000000000009254.0000009,254 km²) |
 |
| Imperial County |
025 |
El Centro |
1907 |
Part of San Diego County.4 |
From the Imperial Valley, which tooks its name from the Imperial Land Company. |
&0000000000142361.000000142,361 |
&0000000000004175.0000004,175 sq mi
(&0000000000010813.00000010,813 km²) |
 |
| Inyo County |
027 |
Independence |
1866 |
Parts of Mono County and Tulare County. |
From a Native American word for dwelling place of the great spirit. |
&0000000000017945.00000017,945 |
&0000000000010192.00000010,192 sq mi
(&0000000000026397.00000026,397 km²) |
 |
| Kern County |
029 |
Bakersfield |
1866 |
Parts of Los Angeles County and Tulare County. |
From the Kern River, named for Edward Kern, cartographer for General John C. Fremont's 1845 expedition. |
&0000000000661645.000000661,645 |
&0000000000008142.0000008,142 sq mi
(&0000000000021088.00000021,088 km²) |
 |
| Kings County |
031 |
Hanford |
1893 |
Part of Tulare County. |
From the Kings River. |
&0000000000129461.000000129,461 |
&0000000000001390.0000001,390 sq mi
(&0000000000003600.0000003,600 km²) |
 |
| Lake County |
033 |
Lakeport |
1861 |
Part of Napa County. |
From Clear Lake. |
&0000000000058309.00000058,309 |
&0000000000001258.0000001,258 sq mi
(&0000000000003258.0000003,258 km²) |
 |
| Lassen County |
035 |
Susanville |
1864 |
Parts of Plumas County and Shasta County, and part of now defunct Lake County, Nevada. |
Named for Peter Lassen (1800-1859), a native of Denmark and an early explorer of the area. |
&0000000000033828.00000033,828 |
&0000000000004558.0000004,558 sq mi
(&0000000000011805.00000011,805 km²) |
 |
| Los Angeles County |
037 |
Los Angeles |
1850 |
One of the twenty-seven original counties. |
Spanish for the Angels or when the Spanish galleons spotted the coastline was covered in morning fog to be reminiscent of entering "heaven". |
&0000000009519338.0000009,519,338 |
&0000000000004060.0000004,060 sq mi
(&0000000000010515.00000010,515 km²) |
 |
| Madera County |
039 |
Madera |
1893 |
Part of Fresno County. |
Spanish for wood or timber. |
&0000000000123109.000000123,109 |
&0000000000002138.0000002,138 sq mi
(&0000000000005537.0000005,537 km²) |
 |
| Marin County |
041 |
San Rafael |
1850 |
One of the twenty-seven original counties. |
Disputed but may have been a corrupted term for Marina for its location on the San Francisco Bay. |
&0000000000247289.000000247,289 |
&0000000000000520.000000520 sq mi
(&0000000000001347.0000001,347 km²) |
 |
| Mariposa County |
043 |
Mariposa |
1850 |
One of the twenty-seven original counties.5 |
Spanish for butterfly. |
&0000000000017130.00000017,130 |
&0000000000001451.0000001,451 sq mi
(&0000000000003758.0000003,758 km²) |
 |
| Mendocino County |
045 |
Ukiah |
1850 |
One of the twenty-seven original counties. |
From Cape Mendocino, named probably for either Antonio de Mendoza or Lorenzo Suárez de Mendoza, viceroys of New Spain. |
&0000000000086265.00000086,265 |
&0000000000003509.0000003,509 sq mi
(&0000000000009088.0000009,088 km²) |
 |
| Merced County |
047 |
Merced |
1855 |
Part of Mariposa County. |
From the Merced River, or in Spanish El Río de Nuestra Señora de la Merced (River of Our Lady of Mercy); named in 1806 by an expedition headed by Gabriel Moraga. |
&0000000000210554.000000210,554 |
&0000000000001929.0000001,929 sq mi
(&0000000000004996.0000004,996 km²) |
 |
| Modoc County |
049 |
Alturas |
1874 |
Part of Siskiyou County. |
From the Native American Modoc people. |
&0000000000009449.0000009,449 |
&0000000000003944.0000003,944 sq mi
(&0000000000010215.00000010,215 km²) |
 |
| Mono County |
051 |
Bridgeport |
1861 |
Parts of Calaveras County, Fresno County and Mariposa County. |
For a local Native American tribe, the Mono Paiute people. |
&0000000000012853.00000012,853 |
&0000000000003044.0000003,044 sq mi
(&0000000000007884.0000007,884 km²) |
 |
| Monterey County |
053 |
Salinas |
1850 |
One of the twenty-seven original counties. |
From Monterey Bay. The name itself is composed of the Spanish words monte (hill) and rey (king). |
&0000000000401762.000000401,762 |
&0000000000003322.0000003,322 sq mi
(&0000000000008604.0000008,604 km²) |
 |
| Napa County |
055 |
Napa |
1850 |
One of the twenty-seven original counties. |
For a local Native American tribe, the Napans. |
&0000000000124279.000000124,279 |
&0000000000000754.000000754 sq mi
(&0000000000001953.0000001,953 km²) |
 |
| Nevada County |
057 |
Nevada City |
1851 |
Part of Yuba County. |
snowfall in Spanish. |
&0000000000092033.00000092,033 |
&0000000000000958.000000958 sq mi
(&0000000000002481.0000002,481 km²) |
 |
| Orange County |
059 |
Santa Ana |
1889 |
Part of Los Angeles County. |
From the citrus fruit widely grown in the region at the time the county was formed. |
&0000000002846289.0000002,846,289 |
&0000000000000790.000000790 sq mi
(&0000000000002046.0000002,046 km²) |
 |
| Placer County |
061 |
Auburn |
1851 |
Parts of Sutter County and Yuba County. |
Named for the small flakes of gold found in the area during Gold Rush. |
&0000000000307004.000000307,004 |
&0000000000001503.0000001,503 sq mi
(&0000000000003893.0000003,893 km²) |
 |
| Plumas County |
063 |
Quincy |
1854 |
Part of Butte County. |
For the Feather River, "Plumas" meaning "feathers" in Spanish. |
&0000000000020824.00000020,824 |
&0000000000002554.0000002,554 sq mi
(&0000000000006615.0000006,615 km²) |
 |
| Riverside County |
065 |
Riverside |
1893 |
Parts of San Bernardino County and San Diego County. |
From the city of Riverside being alongside the Santa Ana River and the boundary extends to the Colorado River. |
&0000000001545387.0000001,545,387 |
&0000000000007208.0000007,208 sq mi
(&0000000000018669.00000018,669 km²) |
 |
| Sacramento County |
067 |
Sacramento |
1850 |
One of the twenty-seven original counties. |
From the Sacramento River, itself named for the Santisimo Sacramento (Spanish for Most Holy Sacrament) a reference to the Eucharist. |
&0000000001223499.0000001,223,499 |
&0000000000000966.000000966 sq mi
(&0000000000002502.0000002,502 km²) |
 |
| San Benito County |
069 |
Hollister |
1874 |
Part of Monterey County. |
in honor of San Benedicto (Saint Benedict), Benito is the diminuative of Benedicto. |
&0000000000053234.00000053,234 |
&0000000000001389.0000001,389 sq mi
(&0000000000003597.0000003,597 km²) |
 |
| San Bernardino County |
071 |
San Bernardino |
1853 |
Part of Los Angeles County. |
Named for Saint Bernardino of Siena. The biggest county in the U.S. |
&0000000001709434.0000001,709,434 |
&0000000000020062.00000020,062 sq mi
(&0000000000051960.00000051,960 km²) |
 |
| San Diego County |
073 |
San Diego |
1850 |
One of the twenty-seven original counties. |
Named for San Diego Bay, itself named for Saint Didacus of Alcalá, or San Diego de Alcalá in Spanish. |
&0000000002813833.0000002,813,833 |
&0000000000004204.0000004,204 sq mi
(&0000000000010888.00000010,888 km²) |
 |
| San Francisco County |
075 |
San Francisco |
1850 |
One of the twenty-seven original counties. |
Francis of Assisi (1181-1226), a Roman Catholic saint and founder of the Order of Friars Minor (Franciscans). |
&0000000000776733.000000776,733 |
&0000000000000047.00000047 sq mi
(&0000000000000122.000000122 km²) |
 |
| San Joaquin County |
077 |
Stockton |
1850 |
One of the twenty-seven original counties. |
Spanish for Saint Joachim. |
&0000000000563598.000000563,598 |
&0000000000001399.0000001,399 sq mi
(&0000000000003623.0000003,623 km²) |
 |
| San Luis Obispo County |
079 |
San Luis Obispo |
1850 |
One of the twenty-seven original counties. |
Spanish for St. Louis, the Bishop. |
&0000000000246681.000000246,681 |
&0000000000003304.0000003,304 sq mi
(&0000000000008557.0000008,557 km²) |
 |
| San Mateo County |
081 |
Redwood City |
1856 |
Part of San Francisco County. |
Spanish for Saint Matthew |
&0000000000707161.000000707,161 |
&0000000000000449.000000449 sq mi
(&0000000000001163.0000001,163 km²) |
 |
| Santa Barbara County |
083 |
Santa Barbara |
1850 |
One of the twenty-seven original counties. |
Spanish for Saint Barbara. |
&0000000000399347.000000399,347 |
&0000000000002738.0000002,738 sq mi
(&0000000000007091.0000007,091 km²) |
 |
| Santa Clara County |
085 |
San Jose |
1850 |
One of the twenty-seven original counties. |
Spanish for Saint Clare, for the Santa Clara Valley and the Mission town of Santa Clara. |
&0000000001682585.0000001,682,585 |
&0000000000001291.0000001,291 sq mi
(&0000000000003344.0000003,344 km²) |
 |
| Santa Cruz County |
087 |
Santa Cruz |
1850 |
One of the twenty-seven original counties. |
Named for the city of Santa Cruz, California but was originally called Branciforte County. |
&0000000000255602.000000255,602 |
&0000000000000446.000000446 sq mi
(&0000000000001155.0000001,155 km²) |
 |
| Shasta County |
089 |
Redding |
1850 |
One of the twenty-seven original counties. |
After Mount Shasta despite the fact the volcanic peak isn't located in the county per se. |
&0000000000163256.000000163,256 |
&0000000000003786.0000003,786 sq mi
(&0000000000009806.0000009,806 km²) |
 |
| Sierra County |
091 |
Downieville |
1852 |
Part of Yuba County. |
Mountain range in Spanish. |
&0000000000003555.0000003,555 |
&0000000000000953.000000953 sq mi
(&0000000000002468.0000002,468 km²) |
 |
| Siskiyou County |
093 |
Yreka |
1852 |
Parts of Shasta County and Klamath County. |
County named after Siskiyou Mountain Range; etymology of Siskiyou is disputed |
&0000000000044301.00000044,301 |
&0000000000006287.0000006,287 sq mi
(&0000000000016283.00000016,283 km²) |
 |
| Solano County |
095 |
Fairfield |
1850 |
One of the twenty-seven original counties. |
After a local Native American tribe, the Solons. |
&0000000000394542.000000394,542 |
&0000000000000828.000000828 sq mi
(&0000000000002145.0000002,145 km²) |
 |
| Sonoma County |
097 |
Santa Rosa |
1850 |
One of the twenty-seven original counties. |
After the village of Sonoma. |
&0000000000458614.000000458,614 |
&0000000000001576.0000001,576 sq mi
(&0000000000004082.0000004,082 km²) |
 |
| Stanislaus County |
099 |
Modesto |
1854 |
Part of Tuolumne County. |
For a Roman Catholic saint Saint Stanislaus. |
&0000000000446997.000000446,997 |
&0000000000001495.0000001,495 sq mi
(&0000000000003872.0000003,872 km²) |
 |
| Sutter County |
101 |
Yuba City |
1850 |
One of the twenty-seven original counties. |
Named for Johann Augustus Sutter (a.k.a. John Sutter) (1803–1880), a Swiss pioneer of California known for his association with the California Gold Rush. His ranch land was originally named Nueva Helvetia after his homeland of Switzerland in Latinized-Spanish. |
&0000000000078930.00000078,930 |
&0000000000000603.000000603 sq mi
(&0000000000001562.0000001,562 km²) |
 |
| Tehama County |
103 |
Red Bluff |
1856 |
Parts of Butte County, Colusa County and Shasta County. |
For a local Native American tribe, the Tehama. |
&0000000000056039.00000056,039 |
&0000000000002951.0000002,951 sq mi
(&0000000000007643.0000007,643 km²) |
 |
| Trinity County |
105 |
Weaverville |
1850 |
One of the twenty-seven original counties. |
To replace an original county, Klamath County, California covered the same area and when the coastal town Trinidad was its county seat.- |
&0000000000013022.00000013,022 |
&0000000000003179.0000003,179 sq mi
(&0000000000008234.0000008,234 km²) |
 |
| Tulare County |
107 |
Visalia |
1852 |
Part of Mariposa County. |
For a dry lake, Tulare Lake on the western end of the county. |
&0000000000368021.000000368,021 |
&0000000000004824.0000004,824 sq mi
(&0000000000012494.00000012,494 km²) |
 |
| Tuolumne County |
109 |
Sonora |
1850 |
One of the twenty-seven original counties. |
For a local Native American tribe, the Tuolomnes. |
&0000000000054501.00000054,501 |
&0000000000002236.0000002,236 sq mi
(&0000000000005791.0000005,791 km²) |
 |
| Ventura County |
111 |
Ventura |
1872 |
Part of Santa Barbara County. |
Abbreviation of San Buenaventura, Spanish for St. Bonaventure. |
&0000000000753197.000000753,197 |
&0000000000001846.0000001,846 sq mi
(&0000000000004781.0000004,781 km²) |
 |
| Yolo County |
113 |
Woodland |
1850 |
One of the twenty-seven original counties. |
For a local Native American tribe, the Yolans. |
&0000000000168660.000000168,660 |
&0000000000001012.0000001,012 sq mi
(&0000000000002621.0000002,621 km²) |
 |
| Yuba County |
115 |
Marysville |
1850 |
One of the twenty-seven original counties. |
For the Yuba family whom owned ranchos in the Sacramento River Valley. |
&0000000000071938.00000071,938 |
&0000000000000630.000000630 sq mi
(&0000000000001632.0000001,632 km²) |
 |