Chatham is a city located in Sangamon County Illinois. With a 2020 population of 13,400, it is the 176th largest city in Illinois and the 2503rd largest city in the United States . Chatham is currently growing at a rate of 1.48% annually and its population has increased by 16.52% since the most recent census, which recorded a population of 11,500 in 2010. Chatham reached it's highest population of 13,400 in 2021. Spanning over 7 miles, Chatham has a population density of 1,835 people per square mile.
The average household income in Chatham is $102,626 with a poverty rate of 4.08%. The median rental costs in recent years comes to $1,043 per month, and the median house value is $188,900. The median age in Chatham is 35.7 years, 36.5 years for males, and 35.2 years for females.