RANKING · 2024 ACS · 56 SHOWN OF 56

Youngest by median age, Montana counties

Montana counties with the youngest median age (2024 ACS). This list covers the 56 counties in Montana that qualify, ranked against each other statewide. The median across all 56 is 44.4. Biggest climber in the top 100 since 2020: Wibaux County, MT, up 22 places to #16.

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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

01▲2Roosevelt County, MTMT10,24230.9−4%

02▼1Big Horn County, MTMT12,75231.9+7%

03▼1Glacier County, MTMT13,46333.4+9%

04Gallatin County, MTMT128,74034.2+11%

05▲1Hill County, MTMT16,16734.50%

06▼1Blaine County, MTMT6,86035.6+3%

07Missoula County, MTMT123,51337.1+12%

08▲3Fallon County, MTMT2,95937.5−9%

09▲6Toole County, MTMT5,21137.7−4%

10▲2Rosebud County, MTMT8,25338.0+10%

11▼3Richland County, MTMT11,37738.4−2%

12▼2Cascade County, MTMT85,02938.6+5%

13▼4Yellowstone County, MTMT172,69239.0+6%

14▲6Liberty County, MTMT1,95739.8−4%

15▲3Silver Bow County, MTMT36,11840.5+4%

16▲22Wibaux County, MTMT88541.0−3%

17Lewis and Clark County, MTMT75,33141.8+10%

18▲1Pondera County, MTMT6,07242.0+9%

19▲2Flathead County, MTMT115,42942.2+8%

20▲9Teton County, MTMT6,49642.3+6%

21▼7Custer County, MTMT12,03442.7+9%

22▼9Chouteau County, MTMT5,86543.0+9%

23▼7Dawson County, MTMT8,69243.0+5%

24▲9Sheridan County, MTMT3,43643.1−4%

25▼2Beaverhead County, MTMT10,04343.2+15%

26▲1Garfield County, MTMT1,14843.3+4%

27▼2Lake County, MTMT33,39244.3+16%

28▼4Valley County, MTMT7,38544.3+6%

29▲8Fergus County, MTMT11,82544.4+5%

30▼4Phillips County, MTMT4,20345.6+12%

31▲1Powell County, MTMT7,15745.8+15%

32▼2Broadwater County, MTMT8,49345.9+11%

33▲2Park County, MTMT18,21446.0+13%

34▲2Wheatland County, MTMT2,10046.2+12%

35▲12Judith Basin County, MTMT2,16246.2+10%

36▲4Stillwater County, MTMT9,44546.7+14%

37▲2Sweet Grass County, MTMT3,76247.0+14%

38▲3Jefferson County, MTMT13,32947.1+17%

39▲6Powder River County, MTMT1,78147.3+12%

40▲4Ravalli County, MTMT48,58248.7+18%

41▲1Deer Lodge County, MTMT9,70949.9+18%

42▲7Mineral County, MTMT5,18550.0+22%

43Carbon County, MTMT11,46650.4+20%

44▲8Golden Valley County, MTMT84450.9+23%

45▲1Musselshell County, MTMT5,58251.3+19%

46▲8Petroleum County, MTMT54851.6+26%

47▼19Treasure County, MTMT72852.0+24%

48▲3Madison County, MTMT10,02652.2+20%

49▲6Lincoln County, MTMT22,32852.8+25%

50▼2Granite County, MTMT3,65853.0+24%

51▼17McCone County, MTMT1,72053.2+25%

52▼21Daniels County, MTMT1,61253.4+14%

53▲3Sanders County, MTMT14,06254.6+24%

54▼32Carter County, MTMT1,38356.9+36%

55▼5Prairie County, MTMT1,11257.8+18%

56▼3Meagher County, MTMT2,13758.3+36%

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UPDATED 2026-09-11 · DATA: US CENSUS BUREAU ACS 5-YEAR ESTIMATES