Ranking of Illinois Counties By Population Density from Census 2020

According to the data from the US 2020 Census, as at April 2020, among all Illinois counties, Cook County had the highest population density per square mile (5.58K people per sqr mile), followed by DuPage County (2.85K people per sqr mile), and Lake County (1.61K people per sqr mile).

On the other hand, Pope County had the lowest population density (10.20 people per sqr mile), followed by Gallatin County (15.32 people per sqr mile), and Schuyler County (15.78 people per sqr mile).

The chart below shows the top 10 counties with high population density, and the table below shows the ranking of all Illinois counties.

You can also see similar ranking of counties information for other states as well as for all counties in the United States.