McHenry County Demographics

A map of McHenry County's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	237,822	238,659	76.1%	76.9%
Hispanic	50,243	46,705	16.1%	15.1%
Multiracial	9,875	10,881	3.2%	3.5%
Asian	9,441	8,669	3.0%	2.8%
Black	4,315	4,073	1.4%	1.3%
Native American/Other	895	1,242	0.3%	0.4%

McHenry County, Illinois has an estimated population of 312,591, a less than 1% change from the 310,229 recorded in the 2020 Census. The population is 76.1% White, 16.1% Hispanic, 3.2% Multiracial, 3.0% Asian, 1.4% Black, and 0.3% Native American/Other. This demographic dot map shows the population of McHenry County, with one dot drawn for each person counted by the Census, color-coded by race.

McHenry has become slightly more racially diverse since the 2020 Census. It is considerably less diverse than Illinois overall. Demographers use a diversity index to measure the probability that two randomly selected individuals belong to different racial or ethnic groups. In McHenry County, that probability was 38.3% in 2020 and 39.3% in the most recent ACS estimates.

McHenry County is ranked the 6th most populous county in Illinois, out of 102 counties. McHenry County was ranked the 6th most populous county in the 2020 Census.

McHenry County's White Population

237,822 residents of McHenry County, or 76.1% of the population, identify as White. The share of White residents in McHenry County is significantly higher than in Illinois overall, where 58.1% of the population is White. McHenry County ranks 79th statewide in terms of White residents as a share of the population, out of 102 counties.

Since the 2020 Census, McHenry County's White population has remained roughly the same. White residents' share of McHenry County's population has decreased from 76.9% to 76.1%.

McHenry County is more White than neighboring Boone County (68% White), Kane County (54% White), DeKalb County (71% White), and DuPage County (62.2% White). McHenry County is less White than neighboring Walworth County (83.1% White).

McHenry County's Black Population

4,315 residents of McHenry County, or 1.4% of the population, identify as Black. The share of Black residents in McHenry County is considerably lower than in Illinois overall, where 13.3% of the population is Black. McHenry County ranks 56th statewide in terms of Black residents as a share of the population, out of 102 counties.

Since the 2020 Census, McHenry County's Black population has grown by an estimated 5.9%. Black residents' share of McHenry County's population has remained roughly unchanged at 1.4%.

McHenry County is more Black than neighboring Walworth County (0.7% Black). McHenry County is less Black than neighboring Boone County (2.3% Black), Kane County (4.7% Black), DeKalb County (6.8% Black), and DuPage County (4.8% Black).

McHenry County's Asian Population

9,441 residents of McHenry County, or 3.0% of the population, identify as Asian. The share of Asian residents in McHenry County is slightly lower than in Illinois overall, where 5.9% of the population is Asian. McHenry County ranks 11th statewide in terms of Asian residents as a share of the population, out of 102 counties.

Since the 2020 Census, McHenry County's Asian population has grown by an estimated 8.9%. Asian residents' share of McHenry County's population has remained roughly unchanged at 3.0%.

McHenry County is more Asian than neighboring Walworth County (0.8% Asian), Boone County (1% Asian), and DeKalb County (2.2% Asian). McHenry County is less Asian than neighboring Kane County (4% Asian), and DuPage County (13% Asian).

McHenry County's Hispanic Population

50,243 residents of McHenry County, or 16.1% of the population, identify as Hispanic. The share of Hispanic residents in McHenry County is slightly lower than in Illinois overall, where 18.8% of the population is Hispanic. McHenry County ranks 9th statewide in terms of Hispanic residents as a share of the population, out of 102 counties.

Since the 2020 Census, McHenry County's Hispanic population has grown by an estimated 7.6%. Hispanic residents' share of McHenry County's population has increased from 15.1% to 16.1%.

McHenry County is more Hispanic than neighboring Walworth County (12.1% Hispanic), and DeKalb County (14.5% Hispanic). McHenry County is less Hispanic than neighboring Boone County (25.6% Hispanic), and Kane County (33.4% Hispanic).

McHenry County's Native American/Other Population

895 residents of McHenry County, or 0.3% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in McHenry County is comparable to the share in Illinois overall, where 0.5% of the population is Native American/Other. McHenry County ranks 54th statewide in terms of Native American/Other residents as a share of the population, out of 102 counties.

Since the 2020 Census, McHenry County's Native American/Other population has declined by an estimated 27.9%. Native American/Other residents' share of McHenry County's population has remained roughly unchanged at 0.3%.

McHenry County is less Native American/Other than neighboring Walworth County (0.4% Native American/Other), Boone County (0.4% Native American/Other), Kane County (0.5% Native American/Other), DeKalb County (0.7% Native American/Other), and DuPage County (0.5% Native American/Other).

McHenry County's Multiracial Population

9,875 residents of McHenry County, or 3.2% of the population, identify as Multiracial. The share of Multiracial residents in McHenry County is comparable to the share in Illinois overall, where 3.4% of the population is Multiracial. McHenry County ranks 44th statewide in terms of Multiracial residents as a share of the population, out of 102 counties.

Since the 2020 Census, McHenry County's Multiracial population has declined by an estimated 9.2%. Multiracial residents' share of McHenry County's population has remained roughly unchanged at 3.2%.

McHenry County is more Multiracial than neighboring Walworth County (2.8% Multiracial), and Boone County (2.8% Multiracial). McHenry County is less Multiracial than neighboring Kane County (3.4% Multiracial), DeKalb County (4.8% Multiracial), and DuPage County (3.5% Multiracial).

Sources: Most recent population estimates are from the 2020-2024 American Community Survey 5-Year Estimates. 2020 population counts and map data are from 2020 Census State Redistricting Data. Geographic data are from Census TIGER/Line Shapefiles.