County in Illinois
McHenry County
About 312,600 people, median household income $104,800.
District lines run through McHenry County, so who represents you here depends on where you live. Search your address to see yours.
Who lives in McHenry County
Census survey estimates for 2020 to 2024, rounded.
People
- Population
- 312,600
- Median age
- 40.7 years
- Under 18
- 23%
- 65 and over
- 17%
- Veterans, of adults
- 6%
- Speak another language at home
- 16%
Race and ethnicity
- Hispanic or Latino, of any race
- 16%
- White, not Hispanic
- 76%
- Black, not Hispanic
- 1%
- Asian, not Hispanic
- 3%
Income and housing
- Median household income
- $104,800
- Below the poverty line
- 6%
- Bachelor's or higher, adults 25+
- 35%
- Owner-occupied homes
- 83%
- Median home value
- $308,000
2024 vote for president
- Donald Trump, Republican
- 51.7%
- Kamala Harris, Democrat
- 46.4%
- Other candidates
- 1.8%
Votes counted, by precinct. Source: MIT Election Data and Science Lab, precinct returns (public domain).
Represent all of McHenry County
McHenry County's districts (14)
U.S. House (4)
- U.S. House District 9
Held by Janice D. Schakowsky, Democratic
Part of McHenry County: 87,633 people in 2020
- U.S. House District 10
Held by Bradley Scott Schneider, Democratic
Part of McHenry County: 44,042 people in 2020
- U.S. House District 11
Held by Bill Foster, Democratic
Part of McHenry County: 164,051 people in 2020
- U.S. House District 16
Held by Darin LaHood, Republican
Part of McHenry County: 14,503 people in 2020
Illinois Senate (4)
- Illinois Senate District 26
Held by Darby Hills, Republican
Part of McHenry County: 22,597 people in 2020
- Illinois Senate District 32
Held by Craig Wilcox, Republican
Part of McHenry County: 153,654 people in 2020
- Illinois Senate District 33
Held by Don DeWitte, Republican
Part of McHenry County: 41,956 people in 2020
- Illinois Senate District 35
Held by Dave Syverson, Republican
Part of McHenry County: 92,022 people in 2020
Illinois House (6)
- Illinois House District 52
Held by Marty McLaughlin, Republican
Part of McHenry County: 22,597 people in 2020
- Illinois House District 63
Held by Steve Reick, Republican
Part of McHenry County: 108,529 people in 2020
- Illinois House District 64
Held by Tom Weber, Republican
Part of McHenry County: 45,125 people in 2020
- Illinois House District 66
Held by Suzanne Ness, Democratic
Part of McHenry County: 41,956 people in 2020
- Illinois House District 69
Held by Joe Sosnowski, Republican
Part of McHenry County: 76,221 people in 2020
- Illinois House District 70
Held by Jeff Keicher, Republican
Part of McHenry County: 15,801 people in 2020
Towns (43)
Cities, villages and unincorporated communities, with the number of people in the county’s part of each at the 2020 Census.
- Crystal Lake40,269
- Lake in the Hills28,982
- McHenry27,135
- Woodstock25,630
- Huntley (part)21,877
- Algonquin (part)21,482
- Cary17,826
- Harvard9,469
- Marengo7,568
- Johnsburg6,355
- Spring Grove5,487
- Island Lake (part)4,700
- Lakewood4,283
- Fox River Grove (part)4,216
- Wonder Lake3,973
- Pistakee Highlands3,237
- Lakemoor (part)2,452
- Richmond2,089
- Oakwood Hills2,076
- Prairie Grove1,963
- Hebron1,368
- Barrington Hills (part)1,248
- Bull Valley1,128
- Port Barrington (part)1,052
19 more towns
- McCullom Lake988
- Ringwood844
- Fox Lake (part)639
- Holiday Hills618
- Union551
- Trout Valley515
- Greenwood324
- Chemung276
- Burtons Bridge226
- Lawrence220
- Ridgefield210
- Hartland157
- Solon Mills133
- Alden113
- Big Foot Prairie65
- Franklinville38
- Harmony20
- Coral16
- Riley10
Source: U.S. Census Bureau, American Community Survey 5-year estimates, 2020–2024; towns and counties from the 2020 Census, Demographic and Housing Characteristics. Figures rounded by us. Retrieved 2026-10-19. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.