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 2018, at 31.5%. Athens County had the lowest, at 15.8%. The median was 22.6% and the figure for Ohio was 22.2%. Source: the U.S. Census Bureau.

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Highest31.5Holmes County
Lowest15.8Athens County
Median22.688 counties
Ohio22.2History

Map of counties, 2018

Adams County: 23.8 %Allen County: 23.3 %Ashland County: 22.7 %Ashtabula County: 21.9 %Athens County: 15.8 %Auglaize County: 23.9 %Belmont County: 19.2 %Brown County: 22.8 %Butler County: 23.7 %Carroll County: 21.1 %Champaign County: 22.8 %Clark County: 22.5 %Clermont County: 23.4 %Clinton County: 22.8 %Columbiana County: 20.4 %Coshocton County: 24.1 %Crawford County: 21.1 %Cuyahoga County: 20.6 %Darke County: 23.7 %Defiance County: 23.3 %Delaware County: 27.2 %Erie County: 20.2 %Fairfield County: 24.4 %Fayette County: 23.4 %Franklin County: 23.1 %Fulton County: 23.7 %Gallia County: 23 %Geauga County: 22.9 %Greene County: 21.1 %Guernsey County: 21.9 %Hamilton County: 22.6 %Hancock County: 22.3 %Hardin County: 22.9 %Harrison County: 21.6 %Henry County: 23.4 %Highland County: 24.1 %Hocking County: 22.2 %Holmes County: 31.5 %Huron County: 23.8 %Jackson County: 23.7 %Jefferson County: 19.3 %Knox County: 22.9 %Lake County: 19.9 %Lawrence County: 22 %Licking County: 23.2 %Logan County: 22.6 %Lorain County: 22 %Lucas County: 22.6 %Madison County: 21.2 %Mahoning County: 19.9 %Marion County: 20.9 %Medina County: 22.5 %Meigs County: 21.8 %Mercer County: 25.4 %Miami County: 23.3 %Monroe County: 20.4 %Montgomery County: 22 %Morgan County: 21.1 %Morrow County: 23.4 %Muskingum County: 22.6 %Noble County: 18.6 %Ottawa County: 18.9 %Paulding County: 24.1 %Perry County: 23.9 %Pickaway County: 22.4 %Pike County: 24 %Portage County: 18.8 %Preble County: 22.7 %Putnam County: 25.5 %Richland County: 21.6 %Ross County: 21.2 %Sandusky County: 22.4 %Scioto County: 21.5 %Seneca County: 22.1 %Shelby County: 25.1 %Stark County: 21.5 %Summit County: 21 %Trumbull County: 20.3 %Tuscarawas County: 22.8 %Union County: 25.7 %Van Wert County: 23.8 %Vinton County: 22.3 %Warren County: 25.3 %Washington County: 19.9 %Wayne County: 24.2 %Williams County: 22.6 %Wood County: 20.8 %Wyandot County: 22.8 %
  • Under 21
  • 21 to 22
  • 22 to 23
  • 23 to 24
  • 24 and over
%, 2018. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

Top 40 counties, 2018

Holmes County: 31.5 %Holmes County31.5Delaware County: 27.2 %Delaware County27.2Union County: 25.7 %Union County25.7Putnam County: 25.5 %Putnam County25.5Mercer County: 25.4 %Mercer County25.4Warren County: 25.3 %Warren County25.3Shelby County: 25.1 %Shelby County25.1Fairfield County: 24.4 %Fairfield County24.4Wayne County: 24.2 %Wayne County24.2Paulding County: 24.1 %Paulding County24.1Coshocton County: 24.1 %Coshocton County24.1Highland County: 24.1 %Highland County24.1Pike County: 24 %Pike County24Auglaize County: 23.9 %Auglaize County23.9Perry County: 23.9 %Perry County23.9Huron County: 23.8 %Huron County23.8Adams County: 23.8 %Adams County23.8Van Wert County: 23.8 %Van Wert County23.8Fulton County: 23.7 %Fulton County23.7Jackson County: 23.7 %Jackson County23.7Darke County: 23.7 %Darke County23.7Butler County: 23.7 %Butler County23.7Henry County: 23.4 %Henry County23.4Morrow County: 23.4 %Morrow County23.4Clermont County: 23.4 %Clermont County23.4Fayette County: 23.4 %Fayette County23.4Miami County: 23.3 %Miami County23.3Allen County: 23.3 %Allen County23.3Defiance County: 23.3 %Defiance County23.3Licking County: 23.2 %Licking County23.2Franklin County: 23.1 %Franklin County23.1Gallia County: 23 %Gallia County23Hardin County: 22.9 %Hardin County22.9Knox County: 22.9 %Knox County22.9Geauga County: 22.9 %Geauga County22.9Brown County: 22.8 %Brown County22.8Wyandot County: 22.8 %Wyandot County22.8Champaign County: 22.8 %Champaign County22.8Tuscarawas County: 22.8 %Tuscarawas County22.8Clinton County: 22.8 %Clinton County22.8Holmes County: 31.5 %Holmes County31.5Delaware County: 27.2 %Delaware County27.2Union County: 25.7 %Union County25.7Putnam County: 25.5 %Putnam County25.5Mercer County: 25.4 %Mercer County25.4Warren County: 25.3 %Warren County25.3Shelby County: 25.1 %Shelby County25.1Fairfield County: 24.4 %Fairfield County24.4Wayne County: 24.2 %Wayne County24.2Paulding County: 24.1 %Paulding County24.1Coshocton County: 24.1 %Coshocton County24.1Highland County: 24.1 %Highland County24.1Pike County: 24 %Pike County24Auglaize County: 23.9 %Auglaize County23.9Perry County: 23.9 %Perry County23.9Huron County: 23.8 %Huron County23.8Adams County: 23.8 %Adams County23.8Van Wert County: 23.8 %Van Wert County23.8Fulton County: 23.7 %Fulton County23.7Jackson County: 23.7 %Jackson County23.7Darke County: 23.7 %Darke County23.7Butler County: 23.7 %Butler County23.7Henry County: 23.4 %Henry County23.4Morrow County: 23.4 %Morrow County23.4Clermont County: 23.4 %Clermont County23.4Fayette County: 23.4 %Fayette County23.4Miami County: 23.3 %Miami County23.3Allen County: 23.3 %Allen County23.3Defiance County: 23.3 %Defiance County23.3Licking County: 23.2 %Licking County23.2Franklin County: 23.1 %Franklin County23.1Gallia County: 23 %Gallia County23Hardin County: 22.9 %Hardin County22.9Knox County: 22.9 %Knox County22.9Geauga County: 22.9 %Geauga County22.9Brown County: 22.8 %Brown County22.8Wyandot County: 22.8 %Wyandot County22.8Champaign County: 22.8 %Champaign County22.8Tuscarawas County: 22.8 %Tuscarawas County22.8Clinton County: 22.8 %Clinton County22.8
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2018 (%)Change on 2017
1Holmes County31.5-0.5 pts
2Delaware County27.2-0.4 pts
3Union County25.7-0 pts
4Putnam County25.5-0 pts
5Mercer County25.4+0.1 pts
6Warren County25.3-0.3 pts
7Shelby County25.1-0.3 pts
8Fairfield County24.4-0 pts
9Wayne County24.2-0.2 pts
10Paulding County24.1-0.1 pts
11Coshocton County24.1+0.2 pts
12Highland County24.1-0.1 pts
13Pike County24-0.1 pts
14Auglaize County23.9-0.2 pts
15Perry County23.9-0.2 pts
16Huron County23.8-0.3 pts
17Adams County23.8-0.2 pts
18Van Wert County23.80 pts
19Fulton County23.7-0.3 pts
19Jackson County23.7-0 pts
21Darke County23.7-0.2 pts
22Butler County23.7-0.1 pts
23Henry County23.40 pts
24Morrow County23.4-0.5 pts
25Clermont County23.4-0.2 pts
26Fayette County23.4-0.3 pts
27Miami County23.3-0 pts
28Allen County23.3-0 pts
29Defiance County23.3-0.1 pts
30Licking County23.2-0.1 pts
31Franklin County23.1-0.1 pts
32Gallia County23-0.1 pts
33Hardin County22.90 pts
34Knox County22.9+0.1 pts
35Geauga County22.9-0.3 pts
36Brown County22.8-0.2 pts
37Wyandot County22.8-0.1 pts
38Champaign County22.8-0.3 pts
39Tuscarawas County22.8-0.1 pts
40Clinton County22.8-0.2 pts
41Ashland County22.7-0.2 pts
42Preble County22.7-0.3 pts
43Muskingum County22.6-0.2 pts
44Williams County22.6-0.1 pts
45Logan County22.6-0.2 pts
46Hamilton County22.6-0.2 pts
47Lucas County22.6-0.2 pts
48Medina County22.5-0.3 pts
49Clark County22.5-0.2 pts
50Sandusky County22.4-0.3 pts
51Pickaway County22.4-0.1 pts
52Hancock County22.3-0.1 pts
53Vinton County22.3-0.2 pts
54Hocking County22.2-0 pts
55Seneca County22.1-0.2 pts
56Lawrence County22-0.1 pts
57Lorain County22-0.2 pts
58Montgomery County22-0.1 pts
59Ashtabula County21.9-0.1 pts
60Guernsey County21.9-0.2 pts
61Meigs County21.8-0.1 pts
62Richland County21.6-0.1 pts
63Harrison County21.60 pts
64Scioto County21.5-0 pts
65Stark County21.5-0.1 pts
66Ross County21.2-0 pts
67Madison County21.2-0 pts
68Morgan County21.1-0 pts
69Crawford County21.1-0.3 pts
70Greene County21.1+0.2 pts
71Carroll County21.1-0 pts
72Summit County21-0.2 pts
73Marion County20.9+0.2 pts
74Wood County20.8+0.1 pts
75Cuyahoga County20.6-0.2 pts
76Monroe County20.4-0.2 pts
77Columbiana County20.4-0.2 pts
78Trumbull County20.3-0.1 pts
79Erie County20.2-0.2 pts
80Lake County19.9-0.3 pts
81Mahoning County19.9-0.1 pts
82Washington County19.9-0.1 pts
83Jefferson County19.3-0.2 pts
84Belmont County19.2-0 pts
85Ottawa County18.9-0.2 pts
86Portage County18.8-0.1 pts
87Noble County18.6-0.1 pts
88Athens County15.8+0.2 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, 2018) [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, 2018. 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=2018. 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, 2018. 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=2018.

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, 2018 [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=2018 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_ohio_by_2018,
  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, 2018}},
  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=2018. 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, 2018
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=2018
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-under-18/ohio-counties?period=2018.
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 31.5% in 2018, according to the U.S. Census Bureau.

Which county has the lowest population under 18?

Athens County, with 15.8% in 2018.

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