More than half of all Americans are currently under 38 years of age. By 2060, however, the majority will be at least 43-years-old, according to Census Bureau projections. Though the United States as a whole is aging rapidly, there are parts of the country where the number of young people is a defining demographic characteristic.
The increasingly aging population is largely the product of a falling birth rate and long-term improvements in life expectancy. Despite this trend, almost every state has at least one county where the median age is far lower than typical. 24/7 Wall St. reviewed median age by county to identify the youngest county in every state. These counties are often urban and include independent cities in Maryland and Virginia that effectively function as counties.
Click here to see the youngest county in every state.
Click here to see our methodology.
Many of the counties on this list are home to large colleges and universities. As the vast majority of the 19.9 million college and university students in the United States are under 25 years old, the presence of a post-secondary institution can reduce the median age of any county. Story County, Iowa, home to Iowa State University; Oktibbeha County, Mississippi, home to Mississippi State University; and Riley County, Kansas, where Kansas State University is located each rank as the youngest county in its state. In these and several other counties on this list, more than one in every four residents are enrolled in college or graduate school.
Some counties on this list skew younger due to a growing number of new families. In the youngest counties in Alaska, Idaho, North Dakota, South Dakota, and Utah, more than one in every 10 residents are under age 5. New families can also drive population growth, and the vast majority of counties on this list are larger now than they were five years ago. In some states, including New Hampshire, New Jersey, and Rhode Island, the youngest county is also the state’s fastest growing county.
Just because a county has the youngest population in the state does not necessarily mean it is younger than the United States as a whole. In both Connecticut and Maine, the median age in the youngest county is higher than the 37.8-year national median. Both Connecticut and Maine rank among the oldest states in the country, with median ages of 40.8 years and 44.3 years respectively.
1. Alabama: Lee County
> Median age: 31.0 years (county), 38.7 years (state)
> Pop. under 18: 21.6% (county), 22.7% (state)
> Population: 156,597
> Life expectancy: 76.5 years
> County seat: Opelika
See all stories featuring: Alabama
[in-text-ad]
2. Alaska: Kusilvak Census Area
> Median age: 24.0 years (borough), 33.9 years (state)
> Pop. under 18: 39.7% (borough), 25.2% (state)
> Population: 8,129
> Life expectancy: 70.8 years
> Largest city: Hooper Bay
See all stories featuring: Alaska
24/7 Wall St.
3. Arizona: Coconino County
> Median age: 30.6 years (county), 37.2 years (state)
> Pop. under 18: 21.5% (county), 23.8% (state)
> Population: 138,639
> Life expectancy: 79.4 years
> County seat: Flagstaff
See all stories featuring: Arizona
4. Arkansas: Washington County
> Median age: 31.5 years (county), 37.9 years (state)
> Pop. under 18: 24.9% (county), 23.7% (state)
> Population: 223,683
> Life expectancy: 78.1 years
> County seat: Fayetteville
See all stories featuring: Arkansas
[in-text-ad-2]
5. California: Tulare County
> Median age: 30.6 years (county), 36.1 years (state)
> Pop. under 18: 31.4% (county), 23.4% (state)
> Population: 458,809
> Life expectancy: 78.3 years
> County seat: Visalia
See all stories featuring: California
6. Colorado: Alamosa County
> Median age: 30.3 years (county), 36.5 years (state)
> Pop. under 18: 24.3% (county), 23% (state)
> Population: 16,345
> Life expectancy: 77.4 years
> County seat: Alamosa
See all stories featuring: Colorado
[in-text-ad]
7. Connecticut: Tolland County
> Median age: 37.9 years (county), 40.8 years (state)
> Pop. under 18: 18.1% (county), 21.2% (state)
> Population: 151,596
> Life expectancy: 81.6 years
> Largest city: Vernon
See all stories featuring: Connecticut
8. Delaware: Kent County
> Median age: 37.3 years (county), 39.8 years (state)
> Pop. under 18: 23.4% (county), 21.6% (state)
> Population: 173,145
> Life expectancy: 77.5 years
> County seat: Dover
See all stories featuring: Delaware
9. Florida: Leon County
> Median age: 30.5 years (county), 41.8 years (state)
> Pop. under 18: 18.8% (county), 20.3% (state)
> Population: 285,890
> Life expectancy: 79.4 years
> County seat: Tallahassee
See all stories featuring: Florida
[in-text-ad-2]
10. Georgia: Chattahoochee County
> Median age: 23.7 years (county), 36.4 years (state)
> Pop. under 18: 22.3% (county), 24.5% (state)
> Population: 11,096
> Life expectancy: 77.1 years
> County seat: Cusseta
See all stories featuring: Georgia
11. Hawaii: Honolulu County
> Median age: 37.6 years (county), 38.8 years (state)
> Pop. under 18: 21.4% (county), 21.6% (state)
> Population: 990,060
> Life expectancy: 81.4 years
> County seat: Honolulu
See all stories featuring: Hawaii
[in-text-ad]
12. Idaho: Madison County
> Median age: 23.5 years (county), 35.9 years (state)
> Pop. under 18: 27.1% (county), 26.2% (state)
> Population: 38,241
> Life expectancy: 81.1 years
> County seat: Rexburg
See all stories featuring: Idaho
13. Illinois: Champaign County
> Median age: 29.7 years (county), 37.7 years (state)
> Pop. under 18: 19.0% (county), 23% (state)
> Population: 207,946
> Life expectancy: 80.3 years
> County seat: Urbana
See all stories featuring: Illinois
14. Indiana: Tippecanoe County
> Median age: 28.1 years (county), 37.5 years (state)
> Pop. under 18: 20.7% (county), 23.9% (state)
> Population: 186,081
> Life expectancy: 79.1 years
> County seat: Lafayette
See all stories featuring: Indiana
[in-text-ad-2]
15. Iowa: Story County
> Median age: 25.9 years (county), 38.1 years (state)
> Pop. under 18: 16.9% (county), 23.4% (state)
> Population: 95,888
> Life expectancy: 82.1 years
> County seat: Nevada
See all stories featuring: Iowa
16. Kansas: Riley County
> Median age: 24.9 years (county), 36.3 years (state)
> Pop. under 18: 16.9% (county), 24.7% (state)
> Population: 75,696
> Life expectancy: 81.5 years
> County seat: Manhattan
See all stories featuring: Kansas
[in-text-ad]
17. Kentucky: Christian County
> Median age: 28.4 years (county), 38.6 years (state)
> Pop. under 18: 27.6% (county), 22.9% (state)
> Population: 72,438
> Life expectancy: 75.6 years
> County seat: Hopkinsville
See all stories featuring: Kentucky
18. Louisiana: Lincoln Parish
> Median age: 27.6 years (parish), 36.4 years (state)
> Pop. under 18: 20.2% (parish), 23.9% (state)
> Population: 47,536
> Life expectancy: 77.4 years
> Parish seat: Ruston
See all stories featuring: Louisiana
19. Maine: Androscoggin County
> Median age: 40.7 years (county), 44.3 years (state)
> Pop. under 18: 21.9% (county), 19.3% (state)
> Population: 107,317
> Life expectancy: 78.3 years
> County seat: Auburn
See all stories featuring: Maine
[in-text-ad-2]
20. Maryland: Baltimore
> Median age: 35.0 years (county), 38.5 years (state)
> Pop. under 18: 21.0% (county), 22.5% (state)
> Population: 619,796
> Life expectancy: 72.1 years
> County seat: N/A
See all stories featuring: Maryland
21. Massachusetts: Suffolk County
> Median age: 32.6 years (county), 39.4 years (state)
> Pop. under 18: 17.0% (county), 20.4% (state)
> Population: 780,685
> Life expectancy: 79.9 years
> County seat: Boston
See all stories featuring: Massachusetts
[in-text-ad]
22. Michigan: Isabella County
> Median age: 27.4 years (county), 39.6 years (state)
> Pop. under 18: 17.4% (county), 22.3% (state)
> Population: 70,572
> Life expectancy: 79.1 years
> County seat: Mount Pleasant
See all stories featuring: Michigan
23. Minnesota: Blue Earth County
> Median age: 30.6 years (county), 37.9 years (state)
> Pop. under 18: 19.7% (county), 23.4% (state)
> Population: 65,767
> Life expectancy: 81.0 years
> County seat: Mankato
See all stories featuring: Minnesota
24. Mississippi: Oktibbeha County
> Median age: 25.4 years (county), 36.9 years (state)
> Pop. under 18: 17.5% (county), 24.3% (state)
> Population: 49,392
> Life expectancy: 77.9 years
> County seat: Starkville
See all stories featuring: Mississippi
[in-text-ad-2]
25. Missouri: Adair County
> Median age: 27.3 years (county), 38.4 years (state)
> Pop. under 18: 18.0% (county), 22.9% (state)
> Population: 25,437
> Life expectancy: 78.0 years
> County seat: Kirksville
See all stories featuring: Missouri
26. Montana: Big Horn County
> Median age: 29.9 years (county), 39.8 years (state)
> Pop. under 18: 33.6% (county), 22% (state)
> Population: 13,290
> Life expectancy: 73.6 years
> County seat: Hardin
See all stories featuring: Montana
[in-text-ad]
27. Nebraska: Thurston County
> Median age: 28.1 years (county), 36.3 years (state)
> Pop. under 18: 35.6% (county), 24.8% (state)
> Population: 7,055
> Life expectancy: 73.9 years
> County seat: Pender
See all stories featuring: Nebraska
24/7 Wall St.
28. Nevada: Elko County
> Median age: 34.1 years (county), 37.7 years (state)
> Pop. under 18: 27.7% (county), 23.2% (state)
> Population: 52,377
> Life expectancy: 78.3 years
> County seat: Elko
See all stories featuring: Nevada
29. New Hampshire: Strafford County
> Median age: 37.0 years (county), 42.7 years (state)
> Pop. under 18: 19.3% (county), 19.8% (state)
> Population: 126,552
> Life expectancy: 79.5 years
> County seat: Dover
See all stories featuring: New Hampshire
[in-text-ad-2]
30. New Jersey: Hudson County
> Median age: 34.9 years (county), 39.6 years (state)
> Pop. under 18: 20.4% (county), 22.3% (state)
> Population: 679,756
> Life expectancy: 80.3 years
> County seat: Jersey City
See all stories featuring: New Jersey
31. New Mexico: Roosevelt County
> Median age: 29.7 years (county), 37.3 years (state)
> Pop. under 18: 24.6% (county), 23.9% (state)
> Population: 19,313
> Life expectancy: 77.9 years
> County seat: Portales
See all stories featuring: New Mexico
[in-text-ad]
32. New York: Tompkins County
> Median age: 30.4 years (county), 38.4 years (state)
> Pop. under 18: 15.2% (county), 21.2% (state)
> Population: 104,415
> Life expectancy: 81.2 years
> County seat: Ithaca
See all stories featuring: New York
33. North Carolina: Onslow County
> Median age: 26.0 years (county), 38.4 years (state)
> Pop. under 18: 24.5% (county), 22.8% (state)
> Population: 192,685
> Life expectancy: 77.6 years
> County seat: Jacksonville
See all stories featuring: North Carolina
34. North Dakota: Sioux County
> Median age: 26.9 years (county), 35.1 years (state)
> Pop. under 18: 37.5% (county), 22.9% (state)
> Population: 4,420
> Life expectancy: 68.6 years
> County seat: Fort Yates
See all stories featuring: North Dakota
[in-text-ad-2]
35. Ohio: Athens County
> Median age: 28.6 years (county), 39.3 years (state)
> Pop. under 18: 15.0% (county), 22.6% (state)
> Population: 65,563
> Life expectancy: 76.9 years
> County seat: Athens
See all stories featuring: Ohio
36. Oklahoma: Payne County
> Median age: 27.2 years (county), 36.3 years (state)
> Pop. under 18: 19.4% (county), 24.5% (state)
> Population: 80,634
> Life expectancy: 78.4 years
> County seat: Stillwater
See all stories featuring: Oklahoma
[in-text-ad]
37. Oregon: Benton County
> Median age: 32.8 years (county), 39.2 years (state)
> Pop. under 18: 16.7% (county), 21.5% (state)
> Population: 88,249
> Life expectancy: 82.1 years
> County seat: Corvallis
See all stories featuring: Oregon
24/7 Wall St.
38. Pennsylvania: Centre County
> Median age: 31.3 years (county), 40.7 years (state)
> Pop. under 18: 15.3% (county), 21% (state)
> Population: 160,646
> Life expectancy: 81.9 years
> County seat: Bellefonte
See all stories featuring: Pennsylvania
39. Rhode Island: Providence County
> Median age: 37.3 years (county), 39.9 years (state)
> Pop. under 18: 20.9% (county), 19.9% (state)
> Population: 633,704
> Life expectancy: 79.3 years
> Largest city: Providence
See all stories featuring: Rhode Island
[in-text-ad-2]
40. South Carolina: Richland County
> Median age: 33.0 years (county), 39.0 years (state)
> Pop. under 18: 21.8% (county), 22.3% (state)
> Population: 404,869
> Life expectancy: 77.4 years
> County seat: Columbia
See all stories featuring: South Carolina
41. South Dakota: Todd County
> Median age: 24.4 years (county), 36.8 years (state)
> Pop. under 18: 40.1% (county), 24.7% (state)
> Population: 10,016
> Life expectancy: 68.5 years
> County seat: Winner
See all stories featuring: South Dakota
[in-text-ad]
42. Tennessee: Montgomery County
> Median age: 30.5 years (county), 38.6 years (state)
> Pop. under 18: 27.0% (county), 22.7% (state)
> Population: 192,120
> Life expectancy: 76.7 years
> County seat: Clarksville
See all stories featuring: Tennessee
43. Texas: Brazos County
> Median age: 25.8 years (county), 34.3 years (state)
> Pop. under 18: 20.6% (county), 26.3% (state)
> Population: 214,231
> Life expectancy: 79.9 years
> County seat: Bryan
See all stories featuring: Texas
44. Utah: Utah County
> Median age: 24.5 years (county), 30.5 years (state)
> Pop. under 18: 34.5% (county), 30.4% (state)
> Population: 576,496
> Life expectancy: 80.8 years
> County seat: Provo
See all stories featuring: Utah
[in-text-ad-2]
45. Vermont: Chittenden County
> Median age: 36.6 years (county), 42.8 years (state)
> Pop. under 18: 18.4% (county), 19.2% (state)
> Population: 160,985
> Life expectancy: 81.4 years
> County seat: Burlington
See all stories featuring: Vermont
46. Virginia: Lexington
> Median age: 21.6 years (county), 38.0 years (state)
> Pop. under 18: 7.6% (county), 22.3% (state)
> Population: 7,113
> Life expectancy: 80.3 years
> County seat: N/A
See all stories featuring: Virginia
[in-text-ad]
47. Washington: Whitman County
> Median age: 24.5 years (county), 37.6 years (state)
> Pop. under 18: 15.1% (county), 22.5% (state)
> Population: 47,794
> Life expectancy: 81.4 years
> County seat: Colfax
See all stories featuring: Washington
48. West Virginia: Monongalia County
> Median age: 30.9 years (county), 42.2 years (state)
> Pop. under 18: 16.3% (county), 20.5% (state)
> Population: 103,715
> Life expectancy: 79.2 years
> County seat: Morgantown
See all stories featuring: West Virginia
49. Wisconsin: Menominee County
> Median age: 31.4 years (county), 39.2 years (state)
> Pop. under 18: 32.4% (county), 22.5% (state)
> Population: 4,506
> Life expectancy: 72.8 years
> County seat: Keshena
See all stories featuring: Wisconsin
[in-text-ad-2]
50. Wyoming: Albany County
> Median age: 27.1 years (county), 37.0 years (state)
> Pop. under 18: 16.4% (county), 23.7% (state)
> Population: 37,944
> Life expectancy: 80.5 years
> County seat: Laramie
See all stories featuring: Wyoming
Methodology:
To identify the youngest county in each state, 24/7 Wall St. reviewed the median age of each U.S. county from the U.S. Census Bureau’s 2017 American Community Survey. Data on the share of residents under 18 years, the share under 5 years, and population changes also came from the ACS. In Alaska, county equivalents are referred to as boroughs or census areas, and in Louisiana, parishes are county equivalents. In counties without a county seat, the most populous city is listed. In our analysis, we included independent cities, which the Census categorizes alongside counties. In counties without a county seat, the most populous city is listed. We did not list a county seat of most populous city for independent cities.
Take This Retirement Quiz To Get Matched With An Advisor Now (Sponsored)
Are you ready for retirement? Planning for retirement can be overwhelming, that’s why it could be a good idea to speak to a fiduciary financial advisor about your goals today.
Start by taking this retirement quiz right here from SmartAsset that will match you with up to 3 financial advisors that serve your area and beyond in 5 minutes. Smart Asset is now matching over 50,000 people a month.
Click here now to get started.
Thank you for reading! Have some feedback for us?
Contact the 24/7 Wall St. editorial team.
Latest from 24/7
