Madison County, Illinois Demographics 2026

Population Overview

Madison County is located in Illinois with a total population of 264,631. It is the 8th most populous county out of 102 in Illinois. The county encompasses 1 Census-designated place.

Age Demographics

The median age in Madison County is 40.2 years. This is 3% higher than the state median of 38.9 years.

Economy, Income & Housing

The median household income in Madison County is $74,800. This is 8% lower than the state median of $81,702. Compared to the national median of $78,538, household income here is 5% lower. The poverty rate stands at 11.3%. This is 4% lower than the state poverty rate of 11.7%. The unemployment rate is 4.7%. This is 18% lower than the state rate of 5.8%. The median home value is $167,900. Housing costs are 33% lower than the state median of $250,500. With a home-value-to-income ratio of just 2.2x, Madison County is one of the most affordable housing markets in the area. 73.6% of occupied housing units are owner-occupied. This homeownership rate is 10% higher than the state average of 66.8%.

Race & Ethnicity

The largest racial or ethnic group in Madison County is White (non-Hispanic), making up 82.4% of the population. Black or African American residents account for 8.6%. The Hispanic or Latino population (4.2%) is well below the state average of 18.5%. The Asian population (1.0%) is well below the state average of 5.8%.

Education

30.8% of residents aged 25 and older hold a bachelor's degree or higher. This is 17% lower than the state rate of 37.2%. Nationally, 35.0% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 93.7%.