Population under 18 in Sangamon County
Population under 18 in Sangamon County was 21% in 2025, according to the U.S. Census Bureau. That is down 0.2 pts from 2024. That is the 49th highest of 102 counties in 2025.
Population under 18 in Sangamon County, 2010 to 2025
All 16 values
| Period | % |
|---|---|
| 2025 | 21 |
| 2024 | 21.1 |
| 2023 | 21.3 |
| 2022 | 21.7 |
| 2021 | 21.7 |
| 2020 | 22 |
| 2019 | 22 |
| 2018 | 22.2 |
| 2017 | 22.4 |
| 2016 | 22.6 |
| 2015 | 22.8 |
| 2014 | 22.9 |
| 2013 | 23 |
| 2012 | 23.2 |
| 2011 | 23.5 |
| 2010 | 23.7 |
Compared with Illinois and United States
| Place | 2025 |
|---|---|
| Sangamon County | 21 |
| Illinois | 20.6 |
| United States | 21.1 |
Rankings
Definition
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.
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
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 (Population under 18, Sangamon County, 2010 to 2025) [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, Population under 18, Sangamon County, 2010 to 2025. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/en/population-under-18/sangamon-county-illinois. 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. Population under 18, Sangamon County, 2010 to 2025. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/en/population-under-18/sangamon-county-illinois.
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, Population under 18, Sangamon County, 2010 to 2025 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/en/population-under-18/sangamon-county-illinois (Accessed: 12 October 2026).
BibTeX
@misc{census_population_under_18_sangamon_2025,
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: Population under 18, Sangamon County, 2010 to 2025}},
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/en/population-under-18/sangamon-county-illinois. 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: Population under 18, Sangamon County, 2010 to 2025
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/en/population-under-18/sangamon-county-illinois
Y2 - 2026/10/12
N1 - Accessed via Invokely, https://invokely.ai/en/population-under-18/sangamon-county-illinois.
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 -
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:
What is the latest population under 18 in Sangamon County? Cite the source.
get_value {"indicator":"population_0_17_share","place":"us-county-17167"}
GET https://invokely.ai/api/v1/value?indicator=population_0_17_share&place=us-county-17167
Questions
What is the population under 18 in Sangamon County?
Population under 18 in Sangamon County was 21% in 2025, according to the U.S. Census Bureau. That is down 0.2 pts from 2024. That is the 49th highest of 102 counties in 2025.
Where does this figure come from?
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 by Invokely on 2026-10-12.
What was the highest population under 18 in Sangamon County?
23.7% in 2010, the highest value since 2010 in this series.
Related statistics for Sangamon County
- Black or African American population share
- Crude death rate, July to June
- Net domestic migration rate, July to June
- Bachelor's degree or higher, population 25 and over
- County house price annual change, sales and refinances
- Covered employment (QCEW)
- Unemployment rate
- Fair Market Rent, three bedrooms (HUD, monthly)
All statistics for Sangamon County | Sangamon County in figures