Grayslake is a city located in Lake County Illinois. With a 2020 population of 20,451, it is the 118th largest city in Illinois and the 1821st largest city in the United States . Grayslake is currently declining at a rate of -0.67% annually and its population has decreased by -2.41% since the most recent census, which recorded a population of 20,957 in 2010. Grayslake reached it's highest population of 21,170 in 2013. Spanning over 11 miles, Grayslake has a population density of 1,862 people per square mile.
The average household income in Grayslake is $112,593 with a poverty rate of 8.39%. The median rental costs in recent years comes to $1,160 per month, and the median house value is $235,400. The median age in Grayslake is 36.7 years, 35.8 years for males, and 38.1 years for females.