Washington County, Illinois Population 2026

Updated April 2026 · US Census ACS 2023 5-Year Estimates · 77th-largest in Illinois

The population of Washington County, Illinois is 13,682 as of the 2023 American Community Survey, making it the 77th-largest county in Illinois. The median household income is $75,652, the median home value is $149,800, and the median age is 44.2.

The population of Washington County has declined 8.0% since 2010 (14,711 → 13,535), a -0.59% annualized rate.

Washington County within Illinois · Source: US Census TIGER/Line via us-atlas

13,682

Population

-0.59%

Annual growth

People / sq mi

$75,652

Median Income

$149,800

Median Home Value

Washington County covers 563 sq mi of land at 24.3 people per square mile.

About Washington County, IL

The poverty rate is what most separates Washington County from the typical county: 4.4% of residents live below the federal poverty line, against 12.4% nationally. Washington County is a county in Illinois with a population of 13,682.

The typical household earns $75,652 a year, near the US median of $78,538. Poverty is among the lowest of comparable US counties, at 4.4% — below the national 12.4%. The typical home is valued at $149,800, with typical rent around $776.

Degree attainment is mid-range for US counties: 24.4% of adults hold a four-year degree, below the national 35.0%. Around 6.6% of workers work from home, below the national 14.0%, and the average commute runs about 26 minutes each way.

Washington County Population History (2010-2024)

The county of Washington County had a population of 14,711 in 2010 and 13,535 in 2024, a -8.0% growth over 14 years. The peak was 14,711 in 2010. Average annual growth rate: -0.59%.

Washington County population, 2010–2024 · Source: U.S. Census Bureau — decennial census & Population Estimates

13,535

Population (2024)

14,711

Population (2010)

14,711

Peak (2010)

-0.59%

Avg Annual Growth

Year	Population	Change	Annual %	Source
2010	14,711	-	-	estimate
2011	14,574	-137	-0.93%	estimate
2012	14,598	+24	+0.16%	estimate
2013	14,411	-187	-1.28%	estimate
2014	14,389	-22	-0.15%	estimate
2015	14,259	-130	-0.90%	estimate
2016	14,176	-83	-0.58%	estimate
2017	13,960	-216	-1.52%	estimate
2018	14,010	+50	+0.36%	estimate
2019	13,926	-84	-0.60%	estimate
2020	13,731	-195	-1.40%	estimate
2021	13,651	-80	-0.58%	estimate
2022	13,650	-1	-0.01%	estimate
2023	13,570	-80	-0.59%	estimate
2024	13,535	-35	-0.26%	estimate

Race & Ethnicity

White	95.6%
Black or African American	0.8%
Asian	0.0%
Hispanic or Latino (any race)	1.4%
Two or More Races	0.0%

Age & Sex

44.2

Median Age

49.2%

Female

50.8%

Male

21.3%

Age 65+

Age Distribution

Under 5

5.0%

5–9

6.2%

10–14

4.8%

15–19

7.3%

20–24

4.6%

25–34

11.0%

35–44

11.9%

45–54

12.3%

55–59

6.4%

60–64

9.1%

65–74

12.3%

75–84

6.9%

85+

2.1%

Children (under 15): 16.0% · Seniors (65+): 21.3%

Income & Poverty

Median household income	$75,652$-6,050 vs state
Mean household income	$89,742
Per-capita income	$38,507
Poverty rate	4.4%-3.8% vs state
Unemployment rate	2.6%
Employment-to-population	61.2%

Top Industries by Employment

Professional & business services

20.6%

Manufacturing

16.4%

Agriculture

9.2%

Finance & real estate

7.9%

Construction

6.7%

Education & health care

5.6%

Retail trade

4.9%

Information

4.3%

The largest employment sector in Washington County is professional & business services, accounting for 20.6% of workers.

How residents commute

0.1%

Drive alone

2.4%

Carpool

82.6%

Public transit

6.6%

Work from home

25.8 min

Avg commute

Housing

$149,800$-100,700 vs state

Median home value

$776

Median rent

81.2%

Homeownership rate

6,402

Total housing units

89.4%

Occupied

10.6%

Vacant

18.8%

Renter-occupied

Social & access

96.7%

With health insurance

91.4%

With broadband internet

16.7%

Foreign-born

9.1%

Veterans (18+)

13.5%

With a disability

97.7%

Speak language other than English at home

Education

93.2%

High School+

24.4%

Bachelor's+

Largest cities in Illinois

Chicago (2,707,648)Aurora (179,867)Joliet (149,785)Naperville (149,424)Rockford (147,649)Elgin (114,106)Springfield (113,714)Peoria (112,126)Waukegan (88,919)Champaign (88,822)All Illinois cities →

Other counties in Illinois

Cook County (5,185,812)DuPage County (927,263)Lake County (711,885)Will County (698,450)Kane County (516,097)McHenry County (311,366)Winnebago County (283,289)Madison County (264,631)St. Clair County (254,777)Champaign County (206,098)All Illinois counties →

Part of Illinois

Illinois demographic profile All Illinois data →

Metro areas in Illinois

Chicago (9,359,555)St. Louis (2,809,414)Davenport (381,864)Peoria (365,773)Rockford (336,605)Champaign (236,196)Springfield (207,386)Bloomington (170,882)All US metros →

County rankings

US Counties by Population Richest US Counties by Median Household Income Expensive US Counties by Home Value Educated US Counties Counties With Highest Poverty Rates Youngest US Counties by Median Age Oldest US Counties by Median Age Cheapest US Counties by Median Home Value Racially Diverse US Counties Counties With Largest Hispanic Population All rankings →

Frequently Asked Questions

Washington County, Illinois has a population of 13,682 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 77th-largest county in Illinois. Population density is 24 people per square mile.

The population of Washington County has declined 8.0% since 2010 (14,711 → 13,535), a -0.59% annualized rate.

The median household income in Washington County, Illinois is $75,652, with mean (average) household income of $89,742 and per-capita income of $38,507. 4.4% of residents live below the federal poverty level.

In Washington County, the largest racial and ethnic groups are White (95.6%), Hispanic or Latino (1.4%), Black or African American (0.8%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.

The median age in Washington County, Illinois is 44.2 years. Residents are 49.2% female and 50.8% male.

The median home value in Washington County is $149,800 and median monthly rent is $776. 81.2% of occupied housing units are owner-occupied. The county has 6,402 total housing units, 10.6% of which are vacant.

The largest employment sector in Washington County, Illinois is professional, scientific, and management services, employing 20.6% of workers. The unemployment rate is 2.6%.

Chicago is among the largest cities associated with Washington County, Illinois, with a population of 2,707,648.