RANKING · 2020 CENSUS · 58 SHOWN OF 58

Most population lost, California counties · 2020

California counties that lost the most residents from the 2010 census to 2020, by raw count of people rather than percentage. This list covers the 58 counties in California that qualify, ranked against each other statewide.

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SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS 2000

01Butte County, CACA209,211-8,368−140%

02Lassen County, CACA28,117-2,165−135%

03Mariposa County, CACA16,918-1,120−140%

04Mono County, CACA12,505-1,007−135%

05Modoc County, CACA8,426-986+331%

06Del Norte County, CACA26,410-867−121%

07Siskiyou County, CACA42,013-824−207%

08Kings County, CACA154,327-496−102%

09Calaveras County, CACA46,605-286−103%

10Plumas County, CACA18,583-217−120%

11Sierra County, CACA3,098-4−102%

12Alpine County, CACA1,043+29−69%

13Tuolumne County, CACA53,160+255−96%

14Colusa County, CACA21,836+420−83%

15Inyo County, CACA18,158+470−240%

16Glenn County, CACA28,141+795−52%

17Napa County, CACA132,949+1,535−89%

18Humboldt County, CACA131,647+1,840−75%

19Trinity County, CACA15,720+2,326−5773%

20Tehama County, CACA64,665+2,366−63%

21Amador County, CACA41,876+2,383−53%

22Nevada County, CACA101,911+3,477−74%

23Lake County, CACA67,772+3,498−54%

24Mendocino County, CACA88,122+3,760−36%

25Sutter County, CACA98,787+4,896−66%

26Shasta County, CACA181,648+4,932−70%

27Sonoma County, CACA486,444+4,985−93%

28Imperial County, CACA181,411+5,174−84%

29Madera County, CACA167,927+5,390−85%

30Santa Cruz County, CACA258,852+8,479−67%

31San Benito County, CACA70,082+8,940−46%

32Yuba County, CACA88,691+9,420+373%

33Marin County, CACA253,694+9,912−42%

34El Dorado County, CACA192,323+10,127−67%

35San Luis Obispo County, CACA282,367+12,787−57%

36Yolo County, CACA224,410+15,554−44%

37Ventura County, CACA830,851+20,525−76%

38Monterey County, CACA433,729+23,978−48%

39Santa Barbara County, CACA442,065+24,334−18%

40Merced County, CACA297,260+25,409−21%

41Tulare County, CACA485,146+30,938−45%

42Stanislaus County, CACA557,719+38,425−50%

43Solano County, CACA455,376+40,147−26%

44San Mateo County, CACA743,568+45,991−20%

45Placer County, CACA442,081+56,307−26%

46San Francisco County, CACA826,079+68,730+30%

47Kern County, CACA927,068+69,604−41%

48Fresno County, CACA1,035,456+78,204−41%

49San Joaquin County, CACA823,815+93,927+13%

50Contra Costa County, CACA1,170,070+116,902−19%

51San Bernardino County, CACA2,224,091+146,444−50%

52Santa Clara County, CACA1,914,391+154,617−16%

53Sacramento County, CACA1,618,460+166,267−9%

54Alameda County, CACA1,636,630+172,082+5%

55Orange County, CACA3,149,507+176,757−59%

56Los Angeles County, CACA9,694,934+195,404−70%

57San Diego County, CACA3,282,248+203,321−36%

58Riverside County, CACA2,544,916+228,544−39%

SHOWING 1–58 OF 58

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU DECENNIAL CENSUS