RANKING · 2025 ESTIMATES · 58 SHOWN OF 58

Most population lost, California counties

California counties that lost the most residents from the 2020 census to 2025, 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

01Los Angeles County, CACA9,694,934-319,075−149%

02San Francisco County, CACA826,079-47,886−191%

03Alameda County, CACA1,636,630-45,723−128%

04Orange County, CACA3,149,507-37,482−109%

05Santa Clara County, CACA1,914,391-21,868−112%

06San Mateo County, CACA743,568-20,874−136%

07San Diego County, CACA3,282,248-16,386−105%

08Ventura County, CACA830,851-12,992−115%

09Santa Cruz County, CACA258,852-12,009−146%

10Marin County, CACA253,694-8,627−150%

11Santa Barbara County, CACA442,065-6,164−121%

12Monterey County, CACA433,729-5,306−112%

13Napa County, CACA132,949-5,070−138%

14Humboldt County, CACA131,647-4,816−165%

15Lassen County, CACA28,117-4,613−174%

16Mendocino County, CACA88,122-3,479−159%

17Tuolumne County, CACA53,160-2,460−141%

18Butte County, CACA209,211-2,421−112%

19Sonoma County, CACA486,444-2,419−103%

20Siskiyou County, CACA42,013-2,063−368%

21Del Norte County, CACA26,410-1,333−133%

22Plumas County, CACA18,583-1,207−211%

23Tehama County, CACA64,665-1,164−118%

24Inyo County, CACA18,158-858+155%

25Sutter County, CACA98,787-846−106%

26Glenn County, CACA28,141-776−147%

27Mono County, CACA12,505-690−124%

28Shasta County, CACA181,648-507−103%

29Trinity County, CACA15,720-392+856%

30Lake County, CACA67,772-391−105%

31Nevada County, CACA101,911-330−102%

32Modoc County, CACA8,426-274+20%

33Mariposa County, CACA16,918-213−108%

34Alpine County, CACA1,043-161−269%

35Sierra County, CACA3,098-138−158%

36San Luis Obispo County, CACA282,367-57−100%

37Colusa County, CACA21,836-3−100%

38El Dorado County, CACA192,323+1,138−96%

39Calaveras County, CACA46,605+1,313−85%

40Amador County, CACA41,876+1,402−72%

41Imperial County, CACA181,411+1,709−95%

42Kings County, CACA154,327+1,841−93%

43Solano County, CACA455,376+1,885−97%

44Contra Costa County, CACA1,170,070+4,143−97%

45Stanislaus County, CACA557,719+4,841−94%

46San Benito County, CACA70,082+5,873−64%

47Yuba County, CACA88,691+7,116+257%

48Yolo County, CACA224,410+8,007−71%

49Madera County, CACA167,927+11,672−67%

50Tulare County, CACA485,146+12,029−79%

51Merced County, CACA297,260+16,058−50%

52Kern County, CACA927,068+17,833−85%

53Fresno County, CACA1,035,456+26,802−80%

54Sacramento County, CACA1,618,460+33,405−82%

55Placer County, CACA442,081+37,342−51%

56San Bernardino County, CACA2,224,091+42,437−85%

57San Joaquin County, CACA823,815+44,582−46%

58Riverside County, CACA2,544,916+126,731−66%

SHOWING 1–58 OF 58

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU POPULATION ESTIMATES