McHenry County, Illinois
McHenry County is a county in Illinois with an estimated population of 312,800 in 2023. 27 cities, towns and Census places in it are indexed here.
Largest places in McHenry County
Crystal Lake 40,861Algonquin 30,134Lake in the Hills 28,661Huntley 28,269McHenry 28,251Woodstock 25,699Cary 17,977Harvard 9,356Island Lake 7,992Marengo 7,608Johnsburg 6,384Spring Grove 5,512Wonder Lake 4,889Fox River Grove 4,619Lakewood 4,267Richmond 2,114Oakwood Hills 2,053Prairie Grove 1,947Port Barrington 1,567Hebron 1,387Bull Valley 1,113McCullom Lake 968Ringwood 821Holiday Hills 607Union 594Trout Valley 509Greenwood 315
About McHenry County
McHenry County is one of the counties of Illinois. County governments in Illinois handle local services such as courts, property records and elections; cities and towns inside the county run their own municipal services. Population figures come from the Census Bureau's Vintage 2023 estimates, which are updated annually.