Counties in New Hampshire by population under 18

Hillsborough County had the highest population under 18 of 10 counties in 2017, at 20.8%. Carroll County had the lowest, at 15.9%. The median was 18.5% and the figure for New Hampshire was 19.3%. Source: the U.S. Census Bureau.

Keep it in a collection in your library.
Lowest15.9Carroll County
Median18.510 counties
New Hampshire19.3History

Map of counties, 2017

Belknap County: 18.3 %Carroll County: 15.9 %Cheshire County: 18.4 %Coos County: 16.6 %Grafton County: 16.4 %Hillsborough County: 20.8 %Merrimack County: 19.3 %Rockingham County: 19.8 %Strafford County: 18.7 %Sullivan County: 19.2 %
  • Under 17
  • 17 to 18
  • 18 to 19
  • 19 and over
%, 2017. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 2017

Hillsborough County: 20.8 %Hillsborough County20.8Rockingham County: 19.8 %Rockingham County19.8Merrimack County: 19.3 %Merrimack County19.3Sullivan County: 19.2 %Sullivan County19.2Strafford County: 18.7 %Strafford County18.7Cheshire County: 18.4 %Cheshire County18.4Belknap County: 18.3 %Belknap County18.3Coos County: 16.6 %Coos County16.6Grafton County: 16.4 %Grafton County16.4Carroll County: 15.9 %Carroll County15.9Hillsborough County: 20.8 %Hillsborough County20.8Rockingham County: 19.8 %Rockingham County19.8Merrimack County: 19.3 %Merrimack County19.3Sullivan County: 19.2 %Sullivan County19.2Strafford County: 18.7 %Strafford County18.7Cheshire County: 18.4 %Cheshire County18.4Belknap County: 18.3 %Belknap County18.3Coos County: 16.6 %Coos County16.6Grafton County: 16.4 %Grafton County16.4Carroll County: 15.9 %Carroll County15.9
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2017 (%)Change on 2016
1Hillsborough County20.8-0.3 pts
2Rockingham County19.8-0.2 pts
3Merrimack County19.3-0.3 pts
4Sullivan County19.2-0.3 pts
5Strafford County18.7-0.3 pts
6Cheshire County18.40 pts
7Belknap County18.3-0.3 pts
8Coos County16.6-0.1 pts
9Grafton County16.4-0.1 pts
10Carroll County15.9-0.3 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 New Hampshire by population under 18, 2017) [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 New Hampshire by population under 18, 2017. 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/new-hampshire-counties?period=2017. 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 New Hampshire by population under 18, 2017. 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/new-hampshire-counties?period=2017.

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 New Hampshire by population under 18, 2017 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-under-18/new-hampshire-counties?period=2017 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_new_hampshire_2017,
  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 New Hampshire by population under 18, 2017}},
  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/new-hampshire-counties?period=2017. 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 New Hampshire by population under 18, 2017
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/new-hampshire-counties?period=2017
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-under-18/new-hampshire-counties?period=2017.
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  - 
Embed this chart

Paste this code into a web page or a blog post. The chart shows the latest figures as they are published, with the source and a link back to this page.

Sites that read oEmbed links, such as WordPress, can show the chart when you paste the link to this page.

Use this data in your AI agent

Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:

Rank Counties in New Hampshire by population under 18 using official data, and cite the source.
rank_places {"indicator":"population_0_17_share","level":"province","within":"New Hampshire","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=population_0_17_share&level=province&within=New%20Hampshire&limit=10

Connect Claude, ChatGPT or Cursor in one step. The trial answers 25 calls a day without an account.

Questions

Which county has the highest population under 18?

Hillsborough County, with 20.8% in 2017, according to the U.S. Census Bureau.

Which county has the lowest population under 18?

Carroll County, with 15.9% in 2017.

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 New Hampshire: more rankings