Illinois Demographics 2026: Population, Income, Race & Trends Explained, Population Review

Population & Growth

Illinois's 12,692,653 residents make it the 6th-most populous US state. Over the long term, the state has been gaining population — +125.4% from 1910 to 2024.

Population density: 229 people per square mile. By comparison, the US national average is roughly 94/sq mi, while New Jersey leads with ~1,260/sq mi and Alaska is the lowest at ~1.3/sq mi.

Race & Ethnicity

By Census ACS classification, Illinois is:

63.3% White (alone)
13.8% Black or African American
0.0% Asian
1.5% Hispanic or Latino (any race)
0.0% two or more races

Hispanic/Latino is counted as an ethnicity separate from race under Census methodology, so totals can exceed 100% in some breakdowns. The full racial composition (including Native Hawaiian, American Indian, etc.) is available on the Illinois state page.

Income & Economy

Median household income in Illinois is $81,702, with per-capita income at $45,104. 8.2% of residents live below the federal poverty line. Unemployment rate: 3.8%.

Income is concentrated in metro counties — see the county-level rankings on the cities ranking page and counties ranking page for sub-state variation.

Age & Households

Median age in Illinois: 38.9 years (US median ~39). The population is 49.4% male and 50.6% female.

Largest Cities in Illinois

Chicago city — population 2,707,648
Aurora city — population 179,867
Joliet city — population 149,785
Naperville city — population 149,424
Rockford city — population 147,649

Largest Counties in Illinois

Cook County — population 5,185,812
DuPage County — population 927,263
Lake County — population 711,885
Will County — population 698,450
Kane County — population 516,097

How Illinois Compares Nationally

By population: ranked 6th of 50 states. By median household income: see the richest states ranking. By population growth: see fastest growing states. By cost of living: see cheapest states to live.

See the complete Illinois state page with full demographic breakdown, age pyramid, languages, education, housing, and commute data →

Frequently Asked Questions

Illinois has a population of 12,692,653 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, ranking 6th among the 50 states. Population density is 229 people per square mile.

Illinois is gaining population, with a +125.4% change since 1910 (5,638,591 → 12,692,653). This is reported via Census ACS rolling 5-year estimates; for monthly/annual estimates between Census years, see the Census Population Estimates Program.

63.3% of Illinois's population identifies as White, 13.8% as Black or African American, 0.0% as Asian, and 1.5% as Hispanic or Latino (any race). Hispanic/Latino is counted as an ethnicity separate from race under Census methodology, so totals may exceed 100%.

Median household income in Illinois is $81,702 per the 2023 ACS. Per-capita income: $45,104. 8.2% of residents live below the federal poverty line.

The median age in Illinois is 38.9 years. The population is 49.4% male and 50.6% female. Age distribution and population pyramids by 5-year age bands are visible on the Illinois state page.

The largest cities in Illinois by population: Chicago city (2,707,648), Aurora city (179,867), Joliet city (149,785), Naperville city (149,424), Rockford city (147,649).

California is the most populous US state at roughly 39 million, followed by Texas (~30M), Florida (~22M), New York (~20M), and Pennsylvania (~13M). Illinois ranks 6th. Detailed rankings update each ACS release cycle.

Across recent Census Population Estimates, West Virginia, Mississippi, Louisiana, and Illinois have shown the largest sustained population declines. Illinois's own trend is gaining. National state-by-state rankings are published annually by the Census Population Estimates Program.

All demographic data on this page comes from the US Census Bureau American Community Survey (ACS) 5-year estimates, currently the 2023 release. Historical population figures use Census Population Estimates Program annual estimates. Data is public domain and freely available at census.gov.