RANKING · 2020 CENSUS · 56 SHOWN OF 56

Most sparsely populated, Montana counties · 2020

Montana counties with the fewest residents per square mile (2020). This list covers the 56 counties in Montana that qualify, ranked against each other statewide. The median across all 56 is 3.

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SAME RANKING BYCities States Metros

YEAR1990 2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION DENSITYVS 2000

01Garfield County, MTMT1,1480−8%

02Petroleum County, MTMT5480+1%

03Carter County, MTMT1,3830+4%

04Powder River County, MTMT1,7811−9%

05Prairie County, MTMT1,1121−9%

06McCone County, MTMT1,7201−13%

07Golden Valley County, MTMT8441−21%

08Treasure County, MTMT7281−11%

09Meagher County, MTMT2,13710%

10Phillips County, MTMT4,2031−8%

11Wibaux County, MTMT8851−12%

12Judith Basin County, MTMT2,1621−13%

13Daniels County, MTMT1,6121−18%

14Liberty County, MTMT1,9571−9%

15Wheatland County, MTMT2,1001−8%

16Chouteau County, MTMT5,8651−1%

17Valley County, MTMT7,3852−1%

18Rosebud County, MTMT8,2532−11%

19Blaine County, MTMT6,86020%

20Beaverhead County, MTMT10,0432+2%

21Fallon County, MTMT2,9592+7%

22Granite County, MTMT3,6582+17%

23Sweet Grass County, MTMT3,7622+2%

24Sheridan County, MTMT3,4362−14%

25Madison County, MTMT10,0262+26%

26Musselshell County, MTMT5,5823+5%

27Toole County, MTMT5,2113−6%

28Big Horn County, MTMT12,7523+4%

29Fergus County, MTMT11,8253−4%

30Teton County, MTMT6,4963−3%

31Powell County, MTMT7,1573−3%

32Custer County, MTMT12,0343+1%

33Pondera County, MTMT6,0724−8%

34Mineral County, MTMT5,1854+17%

35Dawson County, MTMT8,6924−1%

36Sanders County, MTMT14,0624+21%

37Roosevelt County, MTMT10,2425+2%

38Glacier County, MTMT13,4635+4%

39Stillwater County, MTMT9,4455+9%

40Carbon County, MTMT11,4665+10%

41Lincoln County, MTMT22,3285+4%

42Richland County, MTMT11,3776+19%

43Hill County, MTMT16,1676−2%

44Broadwater County, MTMT8,4936+54%

45Park County, MTMT18,2146+10%

46Jefferson County, MTMT13,3297+20%

47Deer Lodge County, MTMT9,709130%

48Ravalli County, MTMT48,58218+22%

49Flathead County, MTMT115,42921+40%

50Lewis and Clark County, MTMT75,33121+27%

51Lake County, MTMT33,39221+17%

52Cascade County, MTMT85,02931+5%

53Missoula County, MTMT123,51345+23%

54Gallatin County, MTMT128,74046+75%

55Silver Bow County, MTMT36,11849+2%

56Yellowstone County, MTMT172,69263+27%

SHOWING 1–56 OF 56

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