Caseyville is a city located in St. Clair County Illinois. Caseyville has a 2020 population of 30,578. Caseyville is currently declining at a rate of -0.64% annually and its population has decreased by -4.60% since the most recent census, which recorded a population of 32,052 in 2010. Caseyville reached it's highest population of 32,059 in 2011.
The average household income in Caseyville is $90,318 with a poverty rate of 7.62%. The median rental costs in recent years comes to $1,061 per month, and the median house value is $139,900. The median age in Caseyville is 38.1 years, 36.3 years for males, and 39.2 years for females.