Topsham is located in Sagadahoc county Maine with a geographic area of 11.0 square miles. The total population in Topsham is 6,246 with 47.1% male and 52.9% female. Children under age 5 represent 5.5% of the population, under age 18 equal 20.6% of the population and over age 65 is 24.3% of the population. The median household income is $71,393, per capita income is $36,336. There are a total of 2,736 housing units with 73.5% owner occupied. Education includes 25.5% of residents that are high school graduates and 44.0% with a bachelor's degree or higher. The average temperature in Topsham in the summer is 68 degrees, and in the winter 25 degrees.