Carrollton is a city in Greene County, Illinois, United States. The population was 2,484 as of the 2010 census. It is the county seat of Greene County.
Carrollton is located in south-central Greene County at 39°17′48″N 90°24′29″W / 39.29667°N 90.40806°W / 39.29667; -90.40806 (39.296662, -90.408059). U.S. Route 67 passes through the city as 5th Street, leading north 35 miles (56 km) to Jacksonville and south 32 miles (51 km) to Alton on the Mississippi River. Illinois Route 108 (Main Street) crosses US 67 in the center of town, leading east 29 miles (47 km) to Carlinville and west 11 miles (18 km) to Kampsville on the Illinois River.
According to the 2010 census, Carrollton has a total area of 1.902 square miles (4.93 km), of which 1.9 square miles (4.92 km) (or 99.89%) is land and 0.002 square miles (0.01 km) (or 0.11%) is water.
It is located 68 miles (109 km) southwest of Springfield, the state capital, and is 60 miles (97 km) north of St. Louis, Missouri. Greene County borders the Metro East area.
As of the census of 2000, there were 2,605 people, 1,077 households, and 724 families residing in the city. The population density was 1,561.2 people per square mile (602.3/km²). There were 1,175 housing units at an average density of 704.2 per square mile (271.7/km²). The racial makeup of the city was 98.77% White, 0.04% African American, 0.23% Native American, 0.31% Asian, 0.08% Pacific Islander, 0.19% from other races, and 0.38% from two or more races. Hispanic or Latino of any race were 0.50% of the population.
There were 1,077 households out of which 31.1% had children under the age of 18 living with them, 53.7% were married couples living together, 9.8% had a female householder with no husband present, and 32.7% were non-families. 29.9% of all households were made up of individuals and 17.6% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 2.92.
In the city, the population was spread out with 23.7% under the age of 18, 8.2% from 18 to 24, 24.3% from 25 to 44, 22.1% from 45 to 64, and 21.7% who were 65 years of age or older. The median age was 40 years. For every 100 females, there were 88.0 males. For every 100 females age 18 and over, there were 83.8 males.
The median income for a household in the city was $30,154, and the median income for a family was $37,368. Males had a median income of $33,194 versus $19,211 for females. The per capita income for the city was $16,340. About 6.4% of families and 9.0% of the population were below the poverty line, including 13.7% of those under age 18 and 8.2% of those age 65 or over.