Somonauk is a city located in Illinois. With a 2020 population of 1,881, it is the 494th largest city in Illinois and the 7840th largest city in the United States . Somonauk is currently growing at a rate of 0.27% annually but its population has decreased by -0.63% since the most recent census, which recorded a population of 1,893 in 2010. Somonauk reached it's highest population of in . Spanning over 2 miles, Somonauk has a population density of 756 people per square mile.
The average household income in Somonauk is $78,471 with a poverty rate of 8.31%. The median rental costs in recent years comes to $988 per month, and the median house value is $168,900. The median age in Somonauk is 38.1 years, 38.3 years for males, and 37.6 years for females.