Cortland township Flag

Cortland township

County:
DeKalb County
County Seat:
No
Area (mi²):
35.029
State:
Illinois

Cortland township is located in DeKalb County, Illinois. Cortland township has a 2026 population of 11,741. Cortland township is currently growing at a rate of 1.11% annually and its population has increased by 4.99% since the most recent census, which recorded a population of 11,183 in 2020.

The median household income in Cortland township is $99,292 with a poverty rate of 6.02%. The median age in Cortland township is 35.1 years: 32.4 years for males, and 37.4 years for females. For every 100 females there are 102.4 males.

11.7K
Total Population
335
Density (mi²)
129 1.11%
Growth

Cortland township Population

Cortland township Population

Data after 2023 is projected based on recent change

Year ↓
Population
Growth
Annual Change
202611,7411291.11%
202511,6121291.12%
202411,4831291.14%
202311,354520.46%
202211,302560.5%
202111,246630.56%
202011,183-6-0.05%
201911,4281191.05%
201811,309810.72%
201711,228630.56%
201611,165420.38%
201511,12300%
201411,123820.74%
201311,041240.22%
201211,017510.47%
201110,966-2-0.02%
201011,004260.24%

Median Age

Overall: 35.1 years
Female: 37.4 years
Male: 32.4 years

Cortland township Adults

There are 8,406 adults, (1,341 of whom are seniors) in Cortland township.

Sex Ratio

Female: 5,588 (49.4%)
Male: 5,724 (50.6%)

Demographics

The racial composition of Cortland township includes 81.6% White, 5.39% Black or African American, and smaller percentages for other race, Asian and multiracial populations.

Population by Race

Race
Population ↓
Percentage (of total)
White9,23181.6%
Two or more races1,14610.13%
Black or African American6105.39%
Other race2622.32%
Asian630.56%
Race
Population ↓
Percentage (of total)
Two or more races6365.62%
Other race2622.32%
White2211.95%
Black or African American760.67%
Race
Population ↓
Percentage (of total)
White9,01079.65%
Black or African American5344.72%
Two or more races5104.51%
Asian630.56%

Cortland township Marital Status

Economics and Income Statistics

Cortland township 's average per capita income is $55,792. Household income levels show a median of $99,292. The poverty rate stands at 6.02%.

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$124,722-
Families$109,484$122,641
Households$99,292$113,752
Non Families$55,795$62,453

$55,792

Average Income

$99,292

Median Household Income

6.02%

Poverty Rate

Nearby Cities

Sources

  1. US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
  2. US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
  3. American Community Survey (2009 - 2013)
  4. Census QuickFacts
  5. Historical Populations of States and Counties (1790 - 1990)