Alton is located in Illinois. Alton, Illinois has population of 26,342. Alton is less family-centric than the surrounding county with 26% of the households with children.
The median household income in Alton, Illinois is $42,389. The median household income for the surrounding county is $63,321 compared to the national median of $66,222. The median age of people living in Alton is 38.2 years.
The average high temperature in July is 88.1 degrees, with an average low temperature in January of 19.4 degrees. The annual precipitation is 38.54.