Clayton is a city located in Adams County Illinois. With a 2020 population of 669, it is the 763rd largest city in Illinois and the 12068th largest city in the United States . Clayton is currently declining at a rate of -0.30% annually and its population has decreased by -5.64% since the most recent census, which recorded a population of 709 in 2010. Clayton reached it's highest population of in . Spanning over 1 miles, Clayton has a population density of 756 people per square mile.
The average household income in Clayton is $43,478 with a poverty rate of 19.42%. The median rental costs in recent years comes to $403 per month, and the median house value is $67,300. The median age in Clayton is 40.3 years, 41.3 years for males, and 39.4 years for females.