Kendall County had the highest median household income of 102 counties in 2021, at $101,816. Alexander County had the lowest, at $39,871. The median was $58,781 and the figure for Illinois was $72,563. Source: the U.S. Census Bureau.
Household income in the past 12 months at the middle of the distribution, in US dollars adjusted to the last year of the period. United States: American Community Survey five-year estimate, where the period shown is the last year of the five-year span.
US dollars. For Spanish places use net_income_per_household (average, EUR).
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. American Community Survey 5-year estimates, table B19013: median household income in the past 12 months. https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b19013.dat. Retrieved 2026-10-08.
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 Illinois by median household income using official data, and cite the source.
rank_places {"indicator":"median_household_income","level":"province","within":"Illinois","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=median_household_income&level=province&within=Illinois&limit=10
Which county has the highest median household income?
Kendall County, with $101,816 in 2021, according to the U.S. Census Bureau.
Which county has the lowest median household income?
Alexander County, with $39,871 in 2021.
Where does this ranking come from?
Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, American Community Survey 5-year estimates, table B19013: median household income in the past 12 months. Retrieved 2026-10-08.
