Alton was originally called East Orange, and under the latter name was laid out in 1875 when the railroad was extended to that point. East Orange was renamed Alton in 1882. Alton was incorporated as a city in 1883.
As of the census of 2010, there were 1,216 people, 478 households, and 338 families living in the city. The population density was. There were 493 housing units at an average density of. The racial makeup of the city was 95.9% White, 0.7% African American, 0.3% Native American, 0.7% Asian, 1.6% from other races, and 0.8% from two or more races. Hispanic or Latino of any race were 4.7% of the population. There were 478 households, of which 33.9% had children under the age of 18 living with them, 63.6% were married couplesliving together, 4.4% had a female householder with no husband present, 2.7% had a male householder with no wife present, and 29.3% were non-families. 24.9% of all households were made up of individuals, and 12.1% had someone living alone who was 65 years of age or older. The average household size was 2.54 and the average family size was 3.07. The median age in the city was 36.6 years. 27.1% of residents were under the age of 18; 7.5% were between the ages of 18 and 24; 23.2% were from 25 to 44; 28.3% were from 45 to 64; and 13.7% were 65 years of age or older. The gender makeup of the city was 49.5% male and 50.5% female.
2000 census
As of the census of 2000, there were 1,095 people, 439 households, and 297 families living in the city. The population density was 735.3 people per square mile. There were 466 housing units at an average density of 312.9 per square mile. The racial makeup of the city was 99.54% White, 0.09% Native American, 0.09% from other races, and 0.27% from two or more races. Hispanic or Latino of any race were 1.10% of the population. There were 439 households, out of which 32.3% had children under the age of 18 living with them, 61.3% were married couples living together, 4.1% had a female householder with no husband present, and 32.3% were non-families. 30.1% of all households were made up of individuals, and 15.7% had someone living alone who was 65 years of age or older. The average household size was 2.49 and the average family size was 3.14. In the city, the population was spread out, with 27.4% under the age of 18, 10.5% from 18 to 24, 26.4% from 25 to 44, 19.8% from 45 to 64, and 15.9% who were 65 years of age or older. The median age was 38 years. For every 100 females, there were 95.5 males. For every 100 females age 18 and over, there were 99.7 males. The median income for a household in the city was $39,911, and the median income for a family was $47,143. Males had a median income of $30,500 versus $19,570 for females. The per capita income for the city was $16,663. About 4.0% of families and 4.2% of the population were below the poverty line, including 2.4% of those under age 18 and 11.3% of those age 65 or over.
