RANKING · 2020 CENSUS · 56 SHOWN OF 56

Youngest by median age, Montana counties · 2020

Montana counties with the youngest median age (2020 ACS). This list covers the 56 counties in Montana that qualify, ranked against each other statewide. The median across all 56 is 45.1.

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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, MTMT12,75231.5+6%

02Glacier County, MTMT13,46332.8+7%

03Roosevelt County, MTMT10,24233.2+3%

04Gallatin County, MTMT128,74033.4+9%

05Blaine County, MTMT6,86034.50%

06Hill County, MTMT16,16735.3+2%

07Missoula County, MTMT123,51337.7+14%

08Richland County, MTMT11,37738.4−2%

09Yellowstone County, MTMT172,69238.8+5%

10Cascade County, MTMT85,02938.9+6%

11Fallon County, MTMT2,95939.0−5%

12Rosebud County, MTMT8,25339.3+14%

13Chouteau County, MTMT5,86540.3+3%

14Custer County, MTMT12,03441.0+4%

15Toole County, MTMT5,21141.0+5%

16Dawson County, MTMT8,69241.3+1%

17Lewis and Clark County, MTMT75,33141.3+9%

18Silver Bow County, MTMT36,11841.8+7%

19Pondera County, MTMT6,07242.1+9%

20Liberty County, MTMT1,95742.1+1%

21Flathead County, MTMT115,42942.9+10%

22Carter County, MTMT1,38343.1+3%

23Beaverhead County, MTMT10,04343.9+17%

24Valley County, MTMT7,38544.1+6%

25Lake County, MTMT33,39244.7+17%

26Phillips County, MTMT4,20344.7+10%

27Garfield County, MTMT1,14844.9+8%

28Treasure County, MTMT72845.0+8%

29Teton County, MTMT6,49645.1+13%

30Broadwater County, MTMT8,49345.7+11%

31Daniels County, MTMT1,61245.8−3%

32Powell County, MTMT7,15745.9+16%

33Sheridan County, MTMT3,43646.0+2%

34McCone County, MTMT1,72046.2+9%

35Park County, MTMT18,21446.9+16%

36Wheatland County, MTMT2,10047.2+14%

37Fergus County, MTMT11,82547.5+12%

38Wibaux County, MTMT88547.8+13%

39Sweet Grass County, MTMT3,76248.4+17%

40Stillwater County, MTMT9,44548.6+19%

41Jefferson County, MTMT13,32949.2+22%

42Deer Lodge County, MTMT9,70949.4+17%

43Carbon County, MTMT11,46650.0+19%

44Ravalli County, MTMT48,58250.2+22%

45Powder River County, MTMT1,78150.8+21%

46Musselshell County, MTMT5,58251.3+19%

47Judith Basin County, MTMT2,16251.4+22%

48Granite County, MTMT3,65852.6+23%

49Mineral County, MTMT5,18552.8+28%

50Prairie County, MTMT1,11252.8+8%

51Madison County, MTMT10,02652.9+22%

52Golden Valley County, MTMT84453.1+28%

53Meagher County, MTMT2,13753.2+24%

54Petroleum County, MTMT54853.4+30%

55Lincoln County, MTMT22,32854.0+28%

56Sanders County, MTMT14,06255.2+25%

SHOWING 1–56 OF 56

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