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Population Review

What is the population of St. Clair County, IL?

St. Clair County in Illinois has a population of 254,777, per Census ACS 5-Year estimates. The median household income is $70,178 and the median age is 39.5.

Context

Counties are the primary administrative subdivisions of states and a stable unit for tracking population. St. Clair County's population reflects everyone within county lines, including residents of incorporated cities and unincorporated areas.

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Related Questions

What is the median household income in St. Clair County, IL?What is the median home value in St. Clair County, IL?What are the demographics of St. Clair County, IL?What is the cost of living in St. Clair County, IL?Is St. Clair County, IL growing?

Frequently Asked Questions

St. Clair County in Illinois has a population of 254,777, per Census ACS 5-Year estimates. The median household income is $70,178 and the median age is 39.5.