Johnson County, Iowa Demographics 2026

Population Overview

Johnson County is located in Iowa with a total population of 154,881. It is the 4th most populous county out of 99 in Iowa. The county encompasses 1 Census-designated place.

Age Demographics

The median age in Johnson County is 30.8 years. This is 20% lower than the state median of 38.6 years.

Economy, Income & Housing

The median household income in Johnson County is $74,721. This is 2% higher than the state median of $73,147. Compared to the national median of $78,538, household income here is 5% lower. The poverty rate stands at 16.7%. This is 52% higher than the state poverty rate of 11.0%. The unemployment rate is 3.6%. The median home value is $293,100. Housing costs are 50% higher than the state median of $195,900. The home-value-to-income ratio is 3.9x. 58.8% of occupied housing units are owner-occupied. This homeownership rate is 18% lower than the state average of 71.5%.

Race & Ethnicity

The largest racial or ethnic group in Johnson County is White (non-Hispanic), making up 75.5% of the population. Black or African American residents account for 7.5%. The Black or African American population is significantly higher than the state average (7.5% vs 3.8%). The Asian population is significantly higher than the state average (5.8% vs 2.4%).

Education

54.6% of residents aged 25 and older hold a bachelor's degree or higher. This places Johnson County in the top 10% of all cities in the state for educational attainment. This is 77% higher than the state rate of 30.9%. Nationally, 35.0% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 96.2%. Notably, 24.0% of adults hold a graduate or professional degree, indicating a highly educated workforce.