Thayer is located in Illinois. Thayer, Illinois has a population of 531. Thayer is more family-centric than the surrounding county with 44% households with children. The county percentage for households with children is 26%.
The median household income in Thayer, Illinois is $75,444. The median household income for the surrounding county is $64,574 compared to the national median of $66,222. The median age of people living in Thayer is 40.6 years.
The average high temperature in July is 87.9 degrees, with an average low temperature in January of 18.4 degrees. The annual precipitation is 37.05.