Round Lake Beach is a city located in Illinois. With a 2020 population of 26,732, it is the 81st largest city in Illinois and the 1442nd largest city in the United States . Round Lake Beach is currently declining at a rate of -0.68% annually and its population has decreased by -5.12% since the most recent census, which recorded a population of 28,175 in 2010. Round Lake Beach reached it's highest population of 28,111 in 2010. Spanning over 5 miles, Round Lake Beach has a population density of 5,298 people per square mile.
The average household income in Round Lake Beach is $85,025 with a poverty rate of 9.81%. The median rental costs in recent years comes to $1,334 per month, and the median house value is $142,900. The median age in Round Lake Beach is 33 years, 30.2 years for males, and 35.2 years for females.