Kankakee County is a county located in the U.S. state of Illinois. According to the 2020 census, it has a population of 107,502. Its county seat is Kankakee. Kankakee County comprises the Kankakee, IL Metropolitan Statistical Area.

Starting in the 1770s, if not earlier, the area that is now Kankakee County was largely populated by the Potawatomi.

French Canadian Settlers came to Kankakee County in 1834, after the federal government signed the Treaty of Camp Tippecanoe in 1832. They were soon joined by migrants from New York and Vermont, mostly locating in Momence, Illinois. In the 1840s, most of the migrants were French Canadians, and they settled in such places as Bourbonnais.

An act of the Illinois Legislature created Kankakee County out of the north part of Iroquois County and the south part of Will County in February 1853. The six original townships were Yellowhead, Rockville, Bourbonnais, Momence, Aroma Park, and Limestone. The population of the new county was about 8,000. In 1855 the two western townships (Norton and Essex) were taken from Vermilion County and added to Kankakee County. The county was named for the Kankakee River.

• 
  Kankakee County at the time of its creation in 1853

According to the U.S. Census Bureau, the county has a total area of 681 square miles (1,760 km), of which 677 square miles (1,750 km) (99.3%) is land and 4.8 square miles (12 km) (0.7%) is water.

Kankakee, Illinois
Climate chart (explanation)
J F M A M J J A S O N D     1.8     31 12     1.6     37 17     2.8     48 28     3.8     61 38     4.5     73 49     4.4     83 59     4.4     86 63     3.1     84 61     3.5     78 52     2.7     65 40     3.4     50 30     2.6     36 19 █ Average max. and min. temperatures in °F █ Precipitation totals in inches Source: The Weather Channel
Metric conversion J F M A M J J A S O N D     45     −1 −11     41     3 −8     71     9 −2     97     16 3     115     23 9     113     28 15     111     30 17     79     29 16     88     26 11     69     18 4     85     10 −1     66     2 −7 █ Average max. and min. temperatures in °C █ Precipitation totals in mm

In recent years, average temperatures in the county seat of Kankakee have ranged from a low of 12 °F (−11 °C) in January to a high of 86 °F (30 °C) in July, although a record low of −29 °F (−34 °C) was recorded in January 1985 and a record high of 107 °F (42 °C) was recorded in August 1988. Average monthly precipitation ranged from 1.62 inches (41 mm) in February to 4.54 inches (115 mm) in May.

• Will County – north
• Lake County, Indiana – northeast
• Newton County, Indiana – east
• Iroquois County – south
• Ford County – southwest
• Livingston County – west
• Grundy County – northwest

Historical population

Census	Pop.	Note	%±
1860	15,412		—
1870	24,352		58.0%
1880	25,047		2.9%
1890	28,732		14.7%
1900	37,154		29.3%
1910	40,752		9.7%
1920	44,920		10.2%
1930	50,095		11.5%
1940	60,877		21.5%
1950	73,524		20.8%
1960	92,063		25.2%
1970	97,250		5.6%
1980	102,926		5.8%
1990	96,255		−6.5%
2000	103,833		7.9%
2010	113,449		9.3%
2020	107,502		−5.2%
2023 (est.)	105,940		−1.5%
U.S. Decennial Census 1790-1960 1900-1990 1990-2000 2010

As of the 2010 United States census, there were 113,449 people, 41,511 households, and 28,680 families residing in the county. The population density was 167.7 inhabitants per square mile (64.7/km). There were 45,246 housing units at an average density of 66.9 per square mile (25.8/km). The racial makeup of the county was 77.6% white, 15.1% black or African American, 0.9% Asian, 0.3% Native American, 4.0% from other races, and 2.1% from two or more races. Those of Hispanic or Latino origin made up 9.0% of the population. In terms of ancestry, 26.5% were German, 14.2% were Irish, 7.4% were English, 6.7% were Italian, 5.8% were Polish, and 3.6% were American.

Of the 41,511 households, 35.2% had children under the age of 18 living with them, 49.1% were married couples living together, 14.7% had a female householder with no husband present, 30.9% were non-families, and 25.5% of all households were made up of individuals. The average household size was 2.61 and the average family size was 3.13. The median age was 36.7 years.

The median income for a household in the county was $50,484 and the median income for a family was $59,998. Males had a median income of $49,858 versus $32,247 for females. The per capita income for the county was $22,888. About 10.8% of families and 15.0% of the population were below the poverty line, including 20.6% of those under age 18 and 8.4% of those age 65 or over.

• Kankakee
• Momence

Kankakee County is divided into seventeen townships:

United States presidential election results for Kankakee County, Illinois

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	28,285	59.19%	18,399	38.50%	1,101	2.30%
2020	28,532	57.02%	20,271	40.51%	1,237	2.47%
2016	25,129	53.12%	18,971	40.10%	3,205	6.78%
2012	23,136	50.68%	21,595	47.30%	923	2.02%
2008	22,527	46.80%	24,750	51.41%	861	1.79%
2004	24,739	54.93%	20,003	44.42%	294	0.65%
2000	20,049	49.89%	19,180	47.73%	954	2.37%
1996	14,595	41.41%	16,820	47.73%	3,826	10.86%
1992	15,411	38.46%	17,229	43.00%	7,431	18.54%
1988	20,316	56.82%	15,147	42.36%	292	0.82%
1984	23,807	60.02%	15,246	38.44%	612	1.54%
1980	23,810	58.25%	14,626	35.78%	2,437	5.96%
1976	23,003	54.63%	18,394	43.68%	711	1.69%
1972	26,866	66.54%	13,434	33.27%	73	0.18%
1968	20,025	52.35%	14,460	37.80%	3,765	9.84%
1964	16,082	43.61%	20,792	56.39%	0	0.00%
1960	20,311	54.23%	17,115	45.70%	26	0.07%
1956	21,993	66.39%	11,088	33.47%	47	0.14%
1952	20,279	61.44%	12,636	38.29%	90	0.27%
1948	15,699	57.71%	11,305	41.56%	197	0.72%
1944	15,256	57.16%	11,342	42.50%	90	0.34%
1940	15,998	53.62%	13,716	45.97%	124	0.42%
1936	10,935	41.21%	13,162	49.60%	2,441	9.20%
1932	10,873	43.86%	13,555	54.67%	364	1.47%
1928	11,905	53.44%	10,247	45.99%	127	0.57%
1924	12,462	67.47%	2,488	13.47%	3,521	19.06%
1920	12,853	79.33%	2,828	17.46%	520	3.21%
1916	10,594	62.28%	6,096	35.84%	319	1.88%
1912	3,178	36.41%	2,532	29.01%	3,018	34.58%
1908	5,999	68.46%	2,461	28.08%	303	3.46%
1904	6,162	74.93%	1,652	20.09%	410	4.99%
1900	5,798	67.44%	2,674	31.10%	125	1.45%
1896	5,471	68.20%	2,370	29.54%	181	2.26%
1892	3,577	54.42%	2,763	42.04%	233	3.54%

Kankakee County is currently considered a Republican-leaning swing county. In the 2008 Presidential Election, Kankakee County voted 52 percent in favor of Illinois native Barack Obama (D), giving 47 percent to John McCain (R). However, in the 2004 Presidential Election, Kankakee County voted 55 percent in favor of George W. Bush (R) and 44 percent for John Kerry (D).

Kankakee County is split between Illinois's 2nd congressional district, represented by Democrat Robin Kelly (D-Matteson), and Illinois's 1st congressional district, represented by Jonathan Jackson (D-Chicago). Kankakee County has produced three governors: Len Small (R), Samuel H. Shapiro (D), and George H. Ryan (R).

In December 2016, Kankakee County became the only county in Illinois to have a Libertarian county board member when Jim Byrne of Bradley left the Republican Party to join the Libertarian Party. In the 2020 general election, Byrne lost reelection to Democratic candidate Heather Bryan, while Libertarian Jacob Collins was elected unopposed on the Libertarian line continuing Kankakee County's distinction of being the only county with a Libertarian board member until Collins opted not to run for reelection in the 2022 general election.

The county is home to Olivet Nazarene University and Kankakee Community College.

Kankakee County is served by the Greater Kankakee Airport. Amtrak runs train service through the city via Kankakee station. The station serves the Illini and Saluki trains to Carbondale as well as the City of New Orleans. The city of Kankakee has local public transit service provided by the River Valley Metro Mass Transit District. Momence and rural Kankakee county are served by SHOW Bus.

• National Register of Historic Places listings in Kankakee County, Illinois

Specific

General

• Forstall, Richard L., ed. (1996). Population of states and counties of the United States: 1790 to 1990 : from the twenty-one decennial censuses. United States Department of Commerce, Bureau of the Census, Population Division. ISBN 0-934213-48-8.

• Official website
• Atlas of Kankakee County from 1883

41°08′N 87°52′W / 41.14°N 87.86°W / 41.14; -87.86