As of the census of 2000, there were 19,843 people, 7,121 households, and 3,966 families residing in the city. The population density was 379.8/km² (983.7/mi²). There were 7,577 housing units at an average density of 145.0/km² (375.6/mi²). The racial makeup of the city was 62.49% White, 31.16% African American, 0.22% Native American, 1.26% Asian, 0.01% Pacific Islander, 2.88% from other races, and 1.98% from two or more races. Hispanic or Latino of any race were 5.64% of the population.

There were 7,121 households out of which 27.2% had children under the age of 18 living with them, 35.0% were married couples living together, 16.5% had a female householder with no husband present, and 44.3% were non-families. 32.1% of all households were made up of individuals and 10.8% had someone living alone who was 65 years of age or older. The average household size was 2.37 and the average family size was 3.01.

In the city the population was spread out with 20.6% under the age of 18, 27.0% from 18 to 24, 26.0% from 25 to 44, 15.1% from 45 to 64, and 11.3% who were 65 years of age or older. The median age was 26 years. For every 100 females there were 87.2 males. For every 100 females age 18 and over, there were 83.7 males.

The median income for a household in the city was $27,559, and the median income for a family was $39,143. Males had a median income of $30,600 versus $23,224 for females. The per capita income for the city was $16,803. About 15.5% of families and 23.4% of the population were below the poverty line, including 26.7% of those under age 18 and 17.0% of those age 65 or over.
The westside and eastside of Carrollton is very poverty-stricken with active gang violence and murders.