Data / Rankings / Population under 18 / Counties in Ohio

Counties in Ohio by population under 18

Holmes County had the highest population under 18 of 88 counties in 2019, at 31%. Athens County had the lowest, at 15.8%. The median was 22.5% and the figure for Ohio was 22.1%. Source: the U.S. Census Bureau.

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Highest31Holmes County
Lowest15.8Athens County
Median22.588 counties
Ohio22.1History

Map of counties, 2019

Adams County: 23.8 %Allen County: 23.2 %Ashland County: 22.6 %Ashtabula County: 21.7 %Athens County: 15.8 %Auglaize County: 23.7 %Belmont County: 19.1 %Brown County: 22.9 %Butler County: 23.5 %Carroll County: 21 %Champaign County: 22.8 %Clark County: 22.3 %Clermont County: 23.1 %Clinton County: 22.3 %Columbiana County: 20.2 %Coshocton County: 24.3 %Crawford County: 21.1 %Cuyahoga County: 20.4 %Darke County: 23.6 %Defiance County: 23.2 %Delaware County: 26.8 %Erie County: 20.1 %Fairfield County: 24.2 %Fayette County: 23.4 %Franklin County: 22.9 %Fulton County: 23.5 %Gallia County: 23.1 %Geauga County: 22.6 %Greene County: 21 %Guernsey County: 21.8 %Hamilton County: 22.4 %Hancock County: 22.1 %Hardin County: 23 %Harrison County: 21.2 %Henry County: 23.3 %Highland County: 23.9 %Hocking County: 21.9 %Holmes County: 31 %Huron County: 23.7 %Jackson County: 23.8 %Jefferson County: 19.3 %Knox County: 22.8 %Lake County: 19.7 %Lawrence County: 21.9 %Licking County: 23.1 %Logan County: 22.6 %Lorain County: 21.8 %Lucas County: 22.5 %Madison County: 20.9 %Mahoning County: 19.8 %Marion County: 20.9 %Medina County: 22.2 %Meigs County: 21.3 %Mercer County: 25.4 %Miami County: 23.3 %Monroe County: 20.1 %Montgomery County: 21.8 %Morgan County: 20.8 %Morrow County: 23.2 %Muskingum County: 22.6 %Noble County: 18.8 %Ottawa County: 18.5 %Paulding County: 23.9 %Perry County: 23.9 %Pickaway County: 22.3 %Pike County: 23.8 %Portage County: 18.6 %Preble County: 22.6 %Putnam County: 25.4 %Richland County: 21.6 %Ross County: 21.2 %Sandusky County: 22.1 %Scioto County: 21.4 %Seneca County: 21.9 %Shelby County: 24.8 %Stark County: 21.4 %Summit County: 20.8 %Trumbull County: 20 %Tuscarawas County: 22.7 %Union County: 25.6 %Van Wert County: 23.7 %Vinton County: 22 %Warren County: 24.9 %Washington County: 19.9 %Wayne County: 24.1 %Williams County: 22.5 %Wood County: 20.7 %Wyandot County: 22.7 %
  • Under 21
  • 21 to 22
  • 22 to 23
  • 23 to 24
  • 24 and over
%, 2019. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

Top 40 counties, 2019

Holmes County: 31 %Holmes County31Delaware County: 26.8 %Delaware County26.8Union County: 25.6 %Union County25.6Putnam County: 25.4 %Putnam County25.4Mercer County: 25.4 %Mercer County25.4Warren County: 24.9 %Warren County24.9Shelby County: 24.8 %Shelby County24.8Coshocton County: 24.3 %Coshocton County24.3Fairfield County: 24.2 %Fairfield County24.2Wayne County: 24.1 %Wayne County24.1Paulding County: 23.9 %Paulding County23.9Perry County: 23.9 %Perry County23.9Highland County: 23.9 %Highland County23.9Pike County: 23.8 %Pike County23.8Adams County: 23.8 %Adams County23.8Jackson County: 23.8 %Jackson County23.8Van Wert County: 23.7 %Van Wert County23.7Auglaize County: 23.7 %Auglaize County23.7Huron County: 23.7 %Huron County23.7Darke County: 23.6 %Darke County23.6Fulton County: 23.5 %Fulton County23.5Butler County: 23.5 %Butler County23.5Fayette County: 23.4 %Fayette County23.4Henry County: 23.3 %Henry County23.3Miami County: 23.3 %Miami County23.3Defiance County: 23.2 %Defiance County23.2Allen County: 23.2 %Allen County23.2Morrow County: 23.2 %Morrow County23.2Clermont County: 23.1 %Clermont County23.1Licking County: 23.1 %Licking County23.1Gallia County: 23.1 %Gallia County23.1Hardin County: 23 %Hardin County23Brown County: 22.9 %Brown County22.9Franklin County: 22.9 %Franklin County22.9Knox County: 22.8 %Knox County22.8Champaign County: 22.8 %Champaign County22.8Tuscarawas County: 22.7 %Tuscarawas County22.7Wyandot County: 22.7 %Wyandot County22.7Preble County: 22.6 %Preble County22.6Geauga County: 22.6 %Geauga County22.6Holmes County: 31 %Holmes County31Delaware County: 26.8 %Delaware County26.8Union County: 25.6 %Union County25.6Putnam County: 25.4 %Putnam County25.4Mercer County: 25.4 %Mercer County25.4Warren County: 24.9 %Warren County24.9Shelby County: 24.8 %Shelby County24.8Coshocton County: 24.3 %Coshocton County24.3Fairfield County: 24.2 %Fairfield County24.2Wayne County: 24.1 %Wayne County24.1Paulding County: 23.9 %Paulding County23.9Perry County: 23.9 %Perry County23.9Highland County: 23.9 %Highland County23.9Pike County: 23.8 %Pike County23.8Adams County: 23.8 %Adams County23.8Jackson County: 23.8 %Jackson County23.8Van Wert County: 23.7 %Van Wert County23.7Auglaize County: 23.7 %Auglaize County23.7Huron County: 23.7 %Huron County23.7Darke County: 23.6 %Darke County23.6Fulton County: 23.5 %Fulton County23.5Butler County: 23.5 %Butler County23.5Fayette County: 23.4 %Fayette County23.4Henry County: 23.3 %Henry County23.3Miami County: 23.3 %Miami County23.3Defiance County: 23.2 %Defiance County23.2Allen County: 23.2 %Allen County23.2Morrow County: 23.2 %Morrow County23.2Clermont County: 23.1 %Clermont County23.1Licking County: 23.1 %Licking County23.1Gallia County: 23.1 %Gallia County23.1Hardin County: 23 %Hardin County23Brown County: 22.9 %Brown County22.9Franklin County: 22.9 %Franklin County22.9Knox County: 22.8 %Knox County22.8Champaign County: 22.8 %Champaign County22.8Tuscarawas County: 22.7 %Tuscarawas County22.7Wyandot County: 22.7 %Wyandot County22.7Preble County: 22.6 %Preble County22.6Geauga County: 22.6 %Geauga County22.6
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2019 (%)Change on 2018
1Holmes County31-0.4 pts
2Delaware County26.8-0.4 pts
3Union County25.6-0.1 pts
4Putnam County25.4-0.1 pts
5Mercer County25.40 pts
6Warren County24.9-0.4 pts
7Shelby County24.8-0.2 pts
8Coshocton County24.3+0.2 pts
9Fairfield County24.2-0.1 pts
10Wayne County24.1-0.1 pts
11Paulding County23.9-0.2 pts
12Perry County23.90 pts
13Highland County23.9-0.2 pts
14Pike County23.8-0.2 pts
15Adams County23.8-0 pts
16Jackson County23.8+0.1 pts
17Van Wert County23.7-0 pts
18Auglaize County23.7-0.2 pts
19Huron County23.7-0.1 pts
20Darke County23.6-0.1 pts
21Fulton County23.5-0.2 pts
22Butler County23.5-0.2 pts
23Fayette County23.4-0 pts
24Henry County23.3-0.1 pts
25Miami County23.3-0 pts
26Defiance County23.2-0.1 pts
27Allen County23.2-0.1 pts
28Morrow County23.2-0.3 pts
29Clermont County23.1-0.3 pts
30Licking County23.1-0.2 pts
31Gallia County23.1+0.1 pts
32Hardin County230 pts
33Brown County22.9+0.1 pts
34Franklin County22.9-0.1 pts
35Knox County22.8-0.1 pts
36Champaign County22.80 pts
37Tuscarawas County22.7-0.1 pts
38Wyandot County22.7-0.2 pts
39Preble County22.6-0 pts
40Geauga County22.6-0.3 pts
41Muskingum County22.6-0 pts
42Logan County22.6-0 pts
43Ashland County22.6-0.2 pts
44Lucas County22.5-0.1 pts
45Williams County22.5-0.2 pts
46Hamilton County22.4-0.2 pts
47Clinton County22.3-0.4 pts
48Clark County22.3-0.2 pts
49Pickaway County22.3-0.1 pts
50Medina County22.2-0.3 pts
51Sandusky County22.1-0.2 pts
52Hancock County22.1-0.2 pts
53Vinton County22-0.2 pts
54Hocking County21.9-0.2 pts
55Seneca County21.9-0.2 pts
56Lawrence County21.9-0.2 pts
57Montgomery County21.8-0.1 pts
58Lorain County21.8-0.2 pts
59Guernsey County21.8-0.1 pts
60Ashtabula County21.7-0.2 pts
61Richland County21.6-0 pts
62Scioto County21.4-0.1 pts
63Stark County21.4-0.1 pts
64Meigs County21.3-0.5 pts
65Harrison County21.2-0.4 pts
66Ross County21.2-0 pts
67Crawford County21.1-0 pts
68Greene County21-0.1 pts
69Carroll County21-0.1 pts
70Madison County20.9-0.3 pts
71Marion County20.9-0.1 pts
72Summit County20.8-0.1 pts
73Morgan County20.8-0.3 pts
74Wood County20.7-0.1 pts
75Cuyahoga County20.4-0.2 pts
76Columbiana County20.2-0.1 pts
77Erie County20.1-0.1 pts
78Monroe County20.1-0.3 pts
79Trumbull County20-0.3 pts
80Washington County19.9+0.1 pts
81Mahoning County19.8-0.1 pts
82Lake County19.7-0.3 pts
83Jefferson County19.30 pts
84Belmont County19.1-0.1 pts
85Noble County18.8+0.2 pts
86Portage County18.6-0.2 pts
87Ottawa County18.5-0.4 pts
88Athens County15.8-0 pts

Other periods

About this ranking

Residents aged 0 to 17 as a percentage of total population on 1 July. United States: Census Bureau county population estimates by age; states and the nation are sums of their counties.

Uses the US age of majority. Not comparable with population_0_14_share, which stops at 14.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Census Bureau. (2026). Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties (Counties in Ohio by population under 18, 2019) [Data set]. Retrieved October 12, 2026, from https://www.census.gov/programs-surveys/popest/data/data-sets.html

MLA 9

Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Counties in Ohio by population under 18, 2019. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/rankings/population-under-18/ohio-counties?period=2019. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Counties in Ohio by population under 18, 2019. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/rankings/population-under-18/ohio-counties?period=2019.

Harvard

U.S. Census Bureau (2026) Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Counties in Ohio by population under 18, 2019 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-under-18/ohio-counties?period=2019 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_ohio_by_2019,
  author = {{U.S. Census Bureau}},
  title = {{Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Counties in Ohio by population under 18, 2019}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www.census.gov/programs-surveys/popest/data/data-sets.html},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/population-under-18/ohio-counties?period=2019. Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Census Bureau
TI  - Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Counties in Ohio by population under 18, 2019
PY  - 2026
DA  - 2026/06/25
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www.census.gov/programs-surveys/popest/data/data-sets.html
L2  - https://invokely.ai/rankings/population-under-18/ohio-counties?period=2019
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-under-18/ohio-counties?period=2019.
N1  - Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
ER  -
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Rank Counties in Ohio by population under 18 using official data, and cite the source.
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Questions

Which county has the highest population under 18?

Holmes County, with 31% in 2019, according to the U.S. Census Bureau.

Which county has the lowest population under 18?

Athens County, with 15.8% in 2019.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Retrieved 2026-10-12.

Population under 18: other rankings

Counties in Ohio: more rankings