Northfield is located in Washington county Maine with a geographic area of square miles. The total population in Northfield is 281 with 52.0% male and 48.0% female. Children under age 5 represent 5.0% of the population, under age 18 equal 19.9% of the population and over age 65 is 14.2% of the population. The median household income is $96,250, per capita income is $59,981. There are a total of 127 housing units with 92.9% owner occupied. Education includes 12.6% of residents that are high school graduates and 42.5% with a bachelor's degree or higher. The average temperature in Northfield in the summer is 68 degrees, and in the winter 25 degrees.