St Peter is located in Illinois. St Peter, Illinois has a population of 346. St Peter is less family-centric than the surrounding county with 23% households with children. The county percentage for households with children is 25%.
The median household income in St Peter, Illinois is $62,596. The median household income for the surrounding county is $49,580 compared to the national median of $66,222. The median age of people living in St Peter is 45.5 years.
The average high temperature in July is 87.92 degrees, with an average low temperature in January of 19.02 degrees. The annual precipitation is 40.51.