Data / Rankings / Population under 18 / Counties in South Dakota

Counties in South Dakota by population under 18

Dewey County had the highest population under 18 of 66 counties in 2024, at 38.8%. Fall River County had the lowest, at 15.4%. The median was 24.1% and the figure for South Dakota was 23.8%. Source: the U.S. Census Bureau.

Highest38.8Dewey County
Lowest15.4Fall River County
Median24.166 counties
South Dakota23.8History

Top 40 counties, 2024

Dewey County: 38.8 %Dewey County38.8Mellette County: 38 %Mellette County38Todd County: 37.8 %Todd County37.8Buffalo County: 36.3 %Buffalo County36.3Oglala Lakota County: 35.7 %Oglala Lakota County35.7Jackson County: 35.6 %Jackson County35.6Corson County: 35.6 %Corson County35.6Hamlin County: 32.9 %Hamlin County32.9Ziebach County: 32.2 %Ziebach County32.2Bennett County: 30.8 %Bennett County30.8Hanson County: 28.4 %Hanson County28.4Charles Mix County: 28.4 %Charles Mix County28.4Clark County: 28.3 %Clark County28.3Roberts County: 28.3 %Roberts County28.3Beadle County: 28.2 %Beadle County28.2Lyman County: 27.2 %Lyman County27.2Moody County: 27.2 %Moody County27.2Turner County: 27.1 %Turner County27.1McCook County: 26.9 %McCook County26.9Marshall County: 26.5 %Marshall County26.5Hutchinson County: 26 %Hutchinson County26Tripp County: 25.8 %Tripp County25.8Faulk County: 25.6 %Faulk County25.6Douglas County: 25.6 %Douglas County25.6Jerauld County: 25.3 %Jerauld County25.3Lincoln County: 25.3 %Lincoln County25.3Sanborn County: 24.9 %Sanborn County24.9Deuel County: 24.7 %Deuel County24.7Aurora County: 24.6 %Aurora County24.6Jones County: 24.6 %Jones County24.6Minnehaha County: 24.6 %Minnehaha County24.6Kingsbury County: 24.5 %Kingsbury County24.5Harding County: 24.2 %Harding County24.2Butte County: 23.9 %Butte County23.9Haakon County: 23.8 %Haakon County23.8Brule County: 23.8 %Brule County23.8Gregory County: 23.4 %Gregory County23.4Walworth County: 23.4 %Walworth County23.4Hughes County: 23.4 %Hughes County23.4Union County: 23.2 %Union County23.2
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2024 (%)Change on 2023
1Dewey County38.8+0.2 pts
2Mellette County38+4.3 pts
3Todd County37.8-1.5 pts
4Buffalo County36.3-1.1 pts
5Oglala Lakota County35.7-0.6 pts
6Jackson County35.6+0.7 pts
7Corson County35.6+0.4 pts
8Hamlin County32.9-0.6 pts
9Ziebach County32.2-0.8 pts
10Bennett County30.8-0.5 pts
11Hanson County28.4-0.2 pts
12Charles Mix County28.4-0.7 pts
13Clark County28.3+0.2 pts
14Roberts County28.3-0.1 pts
15Beadle County28.2+0.3 pts
16Lyman County27.2-0.6 pts
17Moody County27.2+0.4 pts
18Turner County27.1+0.1 pts
19McCook County26.9+0.3 pts
20Marshall County26.5+0.1 pts
21Hutchinson County26+0.3 pts
22Tripp County25.8+0.8 pts
23Faulk County25.6+1 pts
24Douglas County25.6+0.3 pts
25Jerauld County25.3-0.3 pts
26Lincoln County25.3-0.8 pts
27Sanborn County24.9+0.2 pts
28Deuel County24.70 pts
29Aurora County24.6-0.7 pts
30Jones County24.6+1.1 pts
31Minnehaha County24.6-0.1 pts
32Kingsbury County24.5+0.1 pts
33Harding County24.2-0.5 pts
34Butte County23.9-0.3 pts
35Haakon County23.8+0.3 pts
36Brule County23.8-0.1 pts
37Gregory County23.4-0.1 pts
38Walworth County23.4+0.2 pts
39Hughes County23.4-0.4 pts
40Union County23.2-0.5 pts
41Hand County23+0.3 pts
42Grant County22.8+0.3 pts
43Spink County22.7-0.2 pts
44Hyde County22.7+1.2 pts
45Stanley County22.7-1.3 pts
46Brown County22.6-0.3 pts
47Codington County22.2-0.1 pts
48Pennington County22.2-0.1 pts
49Perkins County22.1+0.2 pts
50Miner County22-0.3 pts
51Davison County21.9-0.6 pts
52Day County21.8-0.5 pts
53Edmunds County21.5-0.2 pts
54Meade County21.5-0.6 pts
55Lake County21.3-0.2 pts
56Brookings County20.7-0.1 pts
57Yankton County20.1-0.4 pts
58Campbell County20+0.1 pts
59Potter County19.7+0.3 pts
60Bon Homme County19.1+0.1 pts
61McPherson County18.9-0.1 pts
62Sully County18.1-0.4 pts
63Lawrence County16.8-0.6 pts
64Clay County16.5-0.3 pts
65Custer County16.3-0.3 pts
66Fall River County15.4-0.3 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 South Dakota by population under 18, 2024) [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 South Dakota by population under 18, 2024. 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/south-dakota-counties?period=2024. 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 South Dakota by population under 18, 2024. 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/south-dakota-counties?period=2024.

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 South Dakota by population under 18, 2024 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-under-18/south-dakota-counties?period=2024 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_south_dakota_2024,
  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 South Dakota by population under 18, 2024}},
  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/south-dakota-counties?period=2024. 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 South Dakota by population under 18, 2024
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/south-dakota-counties?period=2024
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-under-18/south-dakota-counties?period=2024.
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 South Dakota by population under 18 using official data, and cite the source.
rank_places {"indicator":"population_0_17_share","level":"province","within":"South Dakota","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=population_0_17_share&level=province&within=South%20Dakota&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?

Dewey County, with 38.8% in 2024, according to the U.S. Census Bureau.

Which county has the lowest population under 18?

Fall River County, with 15.4% in 2024.

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 South Dakota: more rankings