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. MOC-Floyd Valley Community School District is the local school district. The district formed on July 1, 1994 with the merger of the Maurice-Orange City and Floyd Valley districts. Alton houses the district's middle school while elementary and high schools are in Orange City. Spalding Catholic School, which serves elementary grades, is located in a single campus in Alton. It was previously a K-8 school and had multiple campuses, with middle school in Granville, but the Granville campus closed in 2017, and middle school students are now attending Gehlen Catholic School in LeMars. The associated Spalding Catholic High closed in 2013 with students merged into Gehlen Catholic High School.