RANKING · 2010 CENSUS · 56 SHOWN OF 56

Youngest by median age, Montana counties · 2010

Montana counties with the youngest median age (2010 ACS). This list covers the 56 counties in Montana that qualify, ranked against each other statewide. The median across all 56 is 45.8.

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SAME RANKING BYCities States Metros ZIP codes

RELATEDLargest foreign-born population Most residents with a disability Largest veteran population Most uninsured people Largest senior population Most unmarried people

YEAR1990 2000 2010 2020 2024

RANKPLACESTATEPOPMEDIAN AGEVS 2000

01Big Horn County, MTMT12,75230.5+2%

02Roosevelt County, MTMT10,24231.6−2%

03Glacier County, MTMT13,46331.7+4%

04Gallatin County, MTMT128,74032.5+6%

05Missoula County, MTMT123,51334.3+3%

06Blaine County, MTMT6,86035.1+2%

07Hill County, MTMT16,16735.1+2%

08Rosebud County, MTMT8,25336.5+6%

09Yellowstone County, MTMT172,69238.3+4%

10Cascade County, MTMT85,02938.9+6%

11Lewis and Clark County, MTMT75,33140.9+8%

12Flathead County, MTMT115,42941.2+6%

13Lake County, MTMT33,39241.3+8%

14Richland County, MTMT11,37741.3+5%

15Silver Bow County, MTMT36,11841.3+6%

16Chouteau County, MTMT5,86541.5+6%

17Toole County, MTMT5,21141.5+6%

18Beaverhead County, MTMT10,04342.0+12%

19Custer County, MTMT12,03442.1+7%

20Pondera County, MTMT6,07242.8+11%

21Fallon County, MTMT2,95942.9+4%

22Dawson County, MTMT8,69243.5+6%

23Liberty County, MTMT1,95744.6+7%

24Wheatland County, MTMT2,10044.9+8%

25Powell County, MTMT7,15745.1+14%

26Broadwater County, MTMT8,49345.4+10%

27Park County, MTMT18,21445.4+12%

28Stillwater County, MTMT9,44545.7+12%

29Teton County, MTMT6,49645.8+14%

30Deer Lodge County, MTMT9,70946.0+9%

31Ravalli County, MTMT48,58246.0+12%

32Jefferson County, MTMT13,32946.2+15%

33Garfield County, MTMT1,14846.4+12%

34Valley County, MTMT7,38546.4+11%

35Sweet Grass County, MTMT3,76246.6+13%

36Phillips County, MTMT4,20346.8+15%

37Petroleum County, MTMT54847.3+15%

38Fergus County, MTMT11,82547.8+13%

39Carbon County, MTMT11,46648.1+15%

40Judith Basin County, MTMT2,16248.3+15%

41Golden Valley County, MTMT84448.8+18%

42Lincoln County, MTMT22,32848.9+16%

43McCone County, MTMT1,72048.9+15%

44Wibaux County, MTMT88549.0+16%

45Musselshell County, MTMT5,58249.1+14%

46Powder River County, MTMT1,78149.3+17%

47Madison County, MTMT10,02649.8+15%

48Mineral County, MTMT5,18549.8+21%

49Sanders County, MTMT14,06249.8+13%

50Meagher County, MTMT2,13750.1+17%

51Carter County, MTMT1,38350.2+20%

52Sheridan County, MTMT3,43650.3+12%

53Daniels County, MTMT1,61250.4+7%

54Treasure County, MTMT72851.5+23%

55Granite County, MTMT3,65852.1+22%

56Prairie County, MTMT1,11253.6+10%

SHOWING 1–56 OF 56

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