Data / Rankings / Population under 18 / Counties in Michigan

Counties in Michigan by population under 18

St. Joseph County had the highest population under 18 of 83 counties in 2024, at 23.8%. Ontonagon County had the lowest, at 11.8%. The median was 19.3% and the figure for Michigan was 20.6%. Source: the U.S. Census Bureau.

Keep it in a collection in your library.
Highest23.8St. Joseph County
Lowest11.8Ontonagon County
Median19.383 counties
Michigan20.6History

Map of counties, 2024

Alcona County: 13 %Alger County: 14.7 %Allegan County: 22.5 %Alpena County: 18.5 %Antrim County: 16.3 %Arenac County: 17.9 %Baraga County: 17.6 %Barry County: 21.3 %Bay County: 18.9 %Benzie County: 16.4 %Berrien County: 20.5 %Branch County: 23.5 %Calhoun County: 22.2 %Cass County: 20.1 %Charlevoix County: 17.1 %Cheboygan County: 16 %Chippewa County: 18.1 %Clare County: 19.5 %Clinton County: 21 %Crawford County: 18 %Delta County: 18.5 %Dickinson County: 19.4 %Eaton County: 20.5 %Emmet County: 17.1 %Genesee County: 21.4 %Gladwin County: 18.8 %Gogebic County: 16.3 %Grand Traverse County: 18.7 %Gratiot County: 15.9 %Hillsdale County: 21.7 %Houghton County: 19.5 %Huron County: 18.4 %Ingham County: 19.3 %Ionia County: 20.7 %Iosco County: 17.3 %Iron County: 16.8 %Isabella County: 19 %Jackson County: 20.3 %Kalamazoo County: 21 %Kalkaska County: 19.3 %Kent County: 22.8 %Keweenaw County: 15.1 %Lake County: 15.1 %Lapeer County: 19.6 %Leelanau County: 15.3 %Lenawee County: 20.2 %Livingston County: 19.9 %Luce County: 15.3 %Mackinac County: 15.1 %Macomb County: 19.9 %Manistee County: 16.2 %Marquette County: 17.2 %Mason County: 18.3 %Mecosta County: 19.2 %Menominee County: 17.3 %Midland County: 20.9 %Missaukee County: 21.5 %Monroe County: 20.4 %Montcalm County: 20.2 %Montmorency County: 15 %Muskegon County: 21.6 %Newaygo County: 21.6 %Oakland County: 19.6 %Oceana County: 20.8 %Ogemaw County: 17.7 %Ontonagon County: 11.8 %Osceola County: 22.5 %Oscoda County: 19.1 %Otsego County: 20 %Ottawa County: 22.2 %Presque Isle County: 15.2 %Roscommon County: 13.9 %Saginaw County: 20.1 %St. Clair County: 19.6 %St. Joseph County: 23.8 %Sanilac County: 20.4 %Schoolcraft County: 17.3 %Shiawassee County: 20.3 %Tuscola County: 20.1 %Van Buren County: 22.2 %Washtenaw County: 17.4 %Wayne County: 22.8 %Wexford County: 22.3 %
  • Under 16
  • 16 to 18
  • 18 to 19
  • 19 to 20
  • 20 to 21
  • 21 and over
%, 2024. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

Top 40 counties, 2024

St. Joseph County: 23.8 %St. Joseph County23.8Branch County: 23.5 %Branch County23.5Wayne County: 22.8 %Wayne County22.8Kent County: 22.8 %Kent County22.8Osceola County: 22.5 %Osceola County22.5Allegan County: 22.5 %Allegan County22.5Wexford County: 22.3 %Wexford County22.3Van Buren County: 22.2 %Van Buren County22.2Ottawa County: 22.2 %Ottawa County22.2Calhoun County: 22.2 %Calhoun County22.2Hillsdale County: 21.7 %Hillsdale County21.7Muskegon County: 21.6 %Muskegon County21.6Newaygo County: 21.6 %Newaygo County21.6Missaukee County: 21.5 %Missaukee County21.5Genesee County: 21.4 %Genesee County21.4Barry County: 21.3 %Barry County21.3Clinton County: 21 %Clinton County21Kalamazoo County: 21 %Kalamazoo County21Midland County: 20.9 %Midland County20.9Oceana County: 20.8 %Oceana County20.8Ionia County: 20.7 %Ionia County20.7Berrien County: 20.5 %Berrien County20.5Eaton County: 20.5 %Eaton County20.5Sanilac County: 20.4 %Sanilac County20.4Monroe County: 20.4 %Monroe County20.4Jackson County: 20.3 %Jackson County20.3Shiawassee County: 20.3 %Shiawassee County20.3Montcalm County: 20.2 %Montcalm County20.2Lenawee County: 20.2 %Lenawee County20.2Tuscola County: 20.1 %Tuscola County20.1Cass County: 20.1 %Cass County20.1Saginaw County: 20.1 %Saginaw County20.1Otsego County: 20 %Otsego County20Macomb County: 19.9 %Macomb County19.9Livingston County: 19.9 %Livingston County19.9Lapeer County: 19.6 %Lapeer County19.6St. Clair County: 19.6 %St. Clair County19.6Oakland County: 19.6 %Oakland County19.6Clare County: 19.5 %Clare County19.5Houghton County: 19.5 %Houghton County19.5St. Joseph County: 23.8 %St. Joseph County23.8Branch County: 23.5 %Branch County23.5Wayne County: 22.8 %Wayne County22.8Kent County: 22.8 %Kent County22.8Osceola County: 22.5 %Osceola County22.5Allegan County: 22.5 %Allegan County22.5Wexford County: 22.3 %Wexford County22.3Van Buren County: 22.2 %Van Buren County22.2Ottawa County: 22.2 %Ottawa County22.2Calhoun County: 22.2 %Calhoun County22.2Hillsdale County: 21.7 %Hillsdale County21.7Muskegon County: 21.6 %Muskegon County21.6Newaygo County: 21.6 %Newaygo County21.6Missaukee County: 21.5 %Missaukee County21.5Genesee County: 21.4 %Genesee County21.4Barry County: 21.3 %Barry County21.3Clinton County: 21 %Clinton County21Kalamazoo County: 21 %Kalamazoo County21Midland County: 20.9 %Midland County20.9Oceana County: 20.8 %Oceana County20.8Ionia County: 20.7 %Ionia County20.7Berrien County: 20.5 %Berrien County20.5Eaton County: 20.5 %Eaton County20.5Sanilac County: 20.4 %Sanilac County20.4Monroe County: 20.4 %Monroe County20.4Jackson County: 20.3 %Jackson County20.3Shiawassee County: 20.3 %Shiawassee County20.3Montcalm County: 20.2 %Montcalm County20.2Lenawee County: 20.2 %Lenawee County20.2Tuscola County: 20.1 %Tuscola County20.1Cass County: 20.1 %Cass County20.1Saginaw County: 20.1 %Saginaw County20.1Otsego County: 20 %Otsego County20Macomb County: 19.9 %Macomb County19.9Livingston County: 19.9 %Livingston County19.9Lapeer County: 19.6 %Lapeer County19.6St. Clair County: 19.6 %St. Clair County19.6Oakland County: 19.6 %Oakland County19.6Clare County: 19.5 %Clare County19.5Houghton County: 19.5 %Houghton County19.5
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2024 (%)Change on 2023
1St. Joseph County23.8-0 pts
2Branch County23.5-0.3 pts
3Wayne County22.8-0.2 pts
4Kent County22.8-0.2 pts
5Osceola County22.5-0.1 pts
6Allegan County22.5-0.5 pts
7Wexford County22.3-0.4 pts
8Van Buren County22.2-0.3 pts
9Ottawa County22.2-0.4 pts
10Calhoun County22.2-0.4 pts
11Hillsdale County21.7-0.2 pts
12Muskegon County21.6-0.4 pts
13Newaygo County21.6-0.1 pts
14Missaukee County21.5-0.4 pts
15Genesee County21.4-0.3 pts
16Barry County21.3-0.4 pts
17Clinton County21-0.4 pts
18Kalamazoo County21-0.3 pts
19Midland County20.9-0.2 pts
20Oceana County20.8-0.3 pts
21Ionia County20.7-0.3 pts
22Berrien County20.5-0.3 pts
23Eaton County20.5-0.2 pts
24Sanilac County20.4-0.2 pts
25Monroe County20.4-0.2 pts
26Jackson County20.3-0.3 pts
27Shiawassee County20.3-0.2 pts
28Montcalm County20.2-0.4 pts
29Lenawee County20.2-0.3 pts
30Tuscola County20.1-0.3 pts
31Cass County20.1-0.4 pts
32Saginaw County20.1-0.5 pts
33Otsego County20-0.4 pts
34Macomb County19.9-0.1 pts
35Livingston County19.9-0.3 pts
36Lapeer County19.6-0.3 pts
37St. Clair County19.6-0.2 pts
38Oakland County19.6-0.2 pts
39Clare County19.5-0.2 pts
40Houghton County19.5-0 pts
41Dickinson County19.4-0.2 pts
42Kalkaska County19.3-0.1 pts
43Ingham County19.3-0.2 pts
44Mecosta County19.2-0.3 pts
45Oscoda County19.1+0.2 pts
46Isabella County19-0.1 pts
47Bay County18.9-0.2 pts
48Gladwin County18.8-0.2 pts
49Grand Traverse County18.7-0.2 pts
50Delta County18.5-0.2 pts
51Alpena County18.5-0.1 pts
52Huron County18.4-0.1 pts
53Mason County18.3-0.4 pts
54Chippewa County18.1-0.3 pts
55Crawford County18+0.2 pts
56Arenac County17.9-0.4 pts
57Ogemaw County17.7-0.1 pts
58Baraga County17.6-0 pts
59Washtenaw County17.4-0.3 pts
60Menominee County17.3-0.3 pts
61Schoolcraft County17.3-0.4 pts
62Iosco County17.3+0.1 pts
63Marquette County17.2-0.3 pts
64Charlevoix County17.1-0.2 pts
65Emmet County17.1-0.3 pts
66Iron County16.8-0.3 pts
67Benzie County16.4-0.2 pts
68Antrim County16.3-0.2 pts
69Gogebic County16.3-0 pts
70Manistee County16.2-0.2 pts
71Cheboygan County16-0.2 pts
72Gratiot County15.9-1.1 pts
73Leelanau County15.3-0.3 pts
74Luce County15.3-0.4 pts
75Presque Isle County15.2-0 pts
76Lake County15.1+0.2 pts
77Mackinac County15.1-0.3 pts
78Keweenaw County15.1+0.1 pts
79Montmorency County15-0.2 pts
80Alger County14.70 pts
81Roscommon County13.9-0 pts
82Alcona County13-0 pts
83Ontonagon County11.8-0.2 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 Michigan 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 Michigan 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/michigan-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 Michigan 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/michigan-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 Michigan 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/michigan-counties?period=2024 (Accessed: 12 October 2026).

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

St. Joseph County, with 23.8% in 2024, according to the U.S. Census Bureau.

Which county has the lowest population under 18?

Ontonagon County, with 11.8% 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 Michigan: more rankings