Logan County is a county located in the U.S. state of Illinois. According to the 2010 census, it had a population of 30,305. Its county seat is Lincoln.
According to the U.S. Census Bureau, the county has a total area of 619 square miles (1,600 km), of which 618 square miles (1,600 km) is land and 0.9 square miles (2.3 km) (0.1%) is water.
The 2010 census reports there were 30,305 people; 12,107 households; and 7,274 families residing in the county. The population density was 49 people per square mile (19/km²). The racial makeup of the county included the following percentages non-Hispanic: 87.7% White, 7.4% Black or African American, 0.2% Native American, 0.6% Asian, 5 persons Pacific Islander, 12 persons from other races, and 1.1% from two or more races. 2.9% of the population were Hispanic or Latino of any race.
There were 11,070 households out of which 29.7% had children under the age of 18 living with them, 50.3% were married couples living together, 10.6% had a female householder with no husband present, and 34.3% were non-families. 29.4% of all households contained individuals who were 65 years of age or older. The average household size was 2.34 and the average family size was 2.85.
14.4% of the population were living in group quarters including 11.4% of the population institutionalized.
According to the 2010 United States Census, there were 30,305 people, 11,070 households, and 7,274 families residing in the county. The population density was 49.0 inhabitants per square mile (18.9/km). There were 12,107 housing units at an average density of 19.6 per square mile (7.6/km). The racial makeup of the county was 89.1% white, 7.5% black or African American, 0.6% Asian, 0.2% American Indian, 1.2% from other races, and 1.3% from two or more races. Those of Hispanic or Latino origin made up 2.9% of the population. In terms of ancestry, 30.9% were German, 17.4% were American, 13.1% were Irish, and 10.8% were English.
Of the 11,070 households, 29.7% had children under the age of 18 living with them, 50.3% were married couples living together, 10.6% had a female householder with no husband present, 34.3% were non-families, and 29.2% of all households were made up of individuals. The average household size was 2.34 and the average family size was 2.85. The median age was 39.4 years.
The median income for a household in the county was $48,999 and the median income for a family was $63,245. Males had a median income of $43,940 versus $31,783 for females. The per capita income for the county was $22,063. About 6.8% of families and 9.8% of the population were below the poverty line, including 15.1% of those under age 18 and 5.2% of those age 65 or over.