RANKING · 2000 CENSUS · 56 SHOWN OF 56

Most population lost, Montana counties · 2000

Montana counties that lost the most residents from the 1990 census to 2000, by raw count of people rather than percentage. This list covers the 56 counties in Montana that qualify, ranked against each other statewide. The median across all 56 is +221.

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SAME RANKING BYCities States Metros

RELATEDLargest by population Fastest growing Fastest shrinking Most population gained Most densely populated Most sparsely populated

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS –

01Rosebud County, MTMT8,253-1,122–

02Richland County, MTMT11,377-1,049–

03Hill County, MTMT16,167-981–

04Deer Lodge County, MTMT9,709-861–

05Sheridan County, MTMT3,436-627–

06Valley County, MTMT7,385-564–

07Phillips County, MTMT4,203-562–

08Dawson County, MTMT8,692-446–

09Roosevelt County, MTMT10,242-379–

10Garfield County, MTMT1,148-310–

11McCone County, MTMT1,720-299–

12Fallon County, MTMT2,959-266–

13Daniels County, MTMT1,612-249–

14Powder River County, MTMT1,781-232–

15Fergus County, MTMT11,825-190–

16Prairie County, MTMT1,112-184–

17Carter County, MTMT1,383-143–

18Liberty County, MTMT1,957-137–

19Wibaux County, MTMT885-123–

20Petroleum County, MTMT548-26–

21Treasure County, MTMT728-13–

22Pondera County, MTMT6,072-9–

23Custer County, MTMT12,034-1–

24Wheatland County, MTMT2,100+13–

25Judith Basin County, MTMT2,162+47–

26Meagher County, MTMT2,137+113–

27Golden Valley County, MTMT844+130–

28Teton County, MTMT6,496+174–

29Toole County, MTMT5,211+221–

30Blaine County, MTMT6,860+281–

31Granite County, MTMT3,658+282–

32Musselshell County, MTMT5,582+391–

33Sweet Grass County, MTMT3,762+455–

34Chouteau County, MTMT5,865+518–

35Powell County, MTMT7,157+560–

36Mineral County, MTMT5,185+569–

37Silver Bow County, MTMT36,118+665–

38Beaverhead County, MTMT10,043+778–

39Madison County, MTMT10,026+862–

40Broadwater County, MTMT8,493+1,067–

41Glacier County, MTMT13,463+1,126–

42Park County, MTMT18,214+1,132–

43Big Horn County, MTMT12,752+1,334–

44Lincoln County, MTMT22,328+1,356–

45Carbon County, MTMT11,466+1,472–

46Sanders County, MTMT14,062+1,558–

47Stillwater County, MTMT9,445+1,659–

48Jefferson County, MTMT13,329+2,110–

49Cascade County, MTMT85,029+2,666–

50Lake County, MTMT33,392+5,466–

51Lewis and Clark County, MTMT75,331+8,221–

52Ravalli County, MTMT48,582+11,060–

53Flathead County, MTMT115,429+15,253–

54Yellowstone County, MTMT172,692+15,933–

55Missoula County, MTMT123,513+17,115–

56Gallatin County, MTMT128,740+17,368–

SHOWING 1–56 OF 56

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UPDATED 2026-09-11 · DATA: US CENSUS BUREAU DECENNIAL CENSUS