Thomson is located in Carroll county Illinois with a geographic area of 2.2 square miles. The total population in Thomson is 369 with 46.9% male and 53.1% female. Children under age 5 represent 2.2% of the population, under age 18 equal 12.2% of the population and over age 65 is 28.5% of the population. The median household income is $51,071, per capita income is $30,156. There are a total of 190 housing units with 69.5% owner occupied. Education includes 54.7% of residents that are high school graduates and 25.3% with a bachelor's degree or higher. The average temperature in Thomson in the summer is 74 degrees, and in the winter 27 degrees.