Hahnville is a census-designated place (CDP) in and the parish seat of St. Charles Parish, Louisiana, United States. The population was 2,792 at the 2000 census. For information on the origin of Hahnville, see Michael Hahn (1830–1886).
Hahnville is located at 29°58′1″N 90°24′36″W / 29.96694°N 90.41000°W / 29.96694; -90.41000 (29.967081, -90.410129).
According to the United States Census Bureau, the CDP has a total area of 8.8 square miles (23 km), of which 7.8 square miles (20 km) is land and 1.0 square mile (2.6 km) (11.79%) is water.
As of the census of 2000, there were 2,792 people, 987 households, and 752 families residing in the CDP. The population density was 358.8 people per square mile (138.6/km²). There were 1,078 housing units at an average density of 138.5 per square mile (53.5/km²). The racial makeup of the CDP was 47.82% White, 50.90% African American, 0.29% Native American, 0.11% Asian, 0.21% from other races, and 0.68% from two or more races. Hispanic or Latino of any race were 1.15% of the population.
There were 987 households out of which 39.1% had children under the age of 18 living with them, 49.2% were married couples living together, 22.1% had a female householder with no husband present, and 23.8% were non-families. 21.3% of all households were made up of individuals and 6.9% had someone living alone who was 65 years of age or older. The average household size was 2.73 and the average family size was 3.16.
In the CDP, the population was spread out with 28.8% under the age of 18, 8.4% from 18 to 24, 30.9% from 25 to 44, 21.8% from 45 to 64, and 10.1% who were 65 years of age or older. The median age was 34 years. For every 100 females, there were 98.0 males. For every 100 females age 18 and over, there were 96.0 males.
The median income for a household in the CDP was $39,405, and the median income for a family was $42,679. Males had a median income of $36,932 versus $23,625 for females. The per capita income for the CDP was $17,385. About 19.8% of families and 21.6% of the population were below the poverty line, including 36.9% of those under age 18 and 11.9% of those age 65 or over.