Fillmore is located in Montgomery county Illinois with a geographic area of 1.0 square miles. The total population in Fillmore is 296 with 48.3% male and 51.7% female. Children under age 5 represent 3.4% of the population, under age 18 equal 14.9% of the population and over age 65 is 19.6% of the population. The median household income is $48,125, per capita income is $26,008. There are a total of 141 housing units with 82.3% owner occupied. Education includes 51.8% of residents that are high school graduates and 2.8% with a bachelor's degree or higher. The average temperature in Fillmore in the summer is 74 degrees, and in the winter 27 degrees.