Monmouth township

County:: Warren County
County Seat:: No
Area (mi²):: 36.831
State:: Illinois

Monmouth township is located in Warren County, Illinois. Monmouth township has a 2025 population of 9,365. Monmouth township is currently declining at a rate of -1.08% annually and its population has decreased by -5.76% since the most recent census, which recorded a population of 9,937 in 2020.

The average household income in Monmouth township is $81,697 with a poverty rate of 15.17%.The median age in Monmouth township is 35.8 years: 34.5 years for males, and 38.2 years for females.

Demographics

The racial composition of Monmouth township includes 77.25% White, 7.26% other race, 4.21% Black or African American, 3.64% Asian, and smaller percentages for Native American, Native Hawaiian or Pacific Islander and multiracial populations.

Population by Race

Race	Population	Percentage (of total)
White	7,560	77.25%
Other race	711	7.26%
Two or more races	486	4.97%
Black or African American	412	4.21%
Asian	356	3.64%
Native American	197	2.01%
Native Hawaiian or Pacific Islander	65	0.66%

Monmouth township Marital Status

Married

Widowed

Divorced

Separated

Never Married

Economics and Income Statistics

Monmouth township's average per capita income is $41,178. Household income levels show a median of $60,911. The poverty rate stands at 15.17%.

Families: A family includes the owner or renter of the home along with everyone related to them - whether through birth, marriage, or adoption. This includes relatives like spouses, children, parents, siblings, grandparents, and any other family members.

Households: A household includes all the people who occupy a housing unit (such as a house or apartment) as their usual place of residence.

Non Families: A nonfamily household is either someone living alone or when the owner/renter lives with people they aren't related to, like roommates.

Name	Median	Mean
Married Families	$94,533	-
Families	$77,951	$88,786
Households	$60,911	$81,697
Non Families	$40,943	$62,387

$41,178

Average Income

$60,911

Median Household Income

15.17%

Poverty Rate