Lancaster is located in Dallas county Texas with a geographic area of 33.1 square miles. The total population in Lancaster is 39,264 with 44.5% male and 55.5% female. Children under age 5 represent 9.9% of the population, under age 18 equal 31.0% of the population and over age 65 is 9.9% of the population. The median household income is $57,832, per capita income is $24,370. There are a total of 13,646 housing units with 63.4% owner occupied. Education includes 22.7% of residents that are high school graduates and 27.4% with a bachelor's degree or higher. The average temperature in Lancaster in the summer is 82 degrees, and in the winter 49 degrees.