Lincoln is located in Placer county California with a geographic area of 24.2 square miles. The total population in Lincoln is 48,150 with 47.6% male and 52.4% female. Children under age 5 represent 5.7% of the population, under age 18 equal 22.6% of the population and over age 65 is 27.6% of the population. The median household income is $88,991, per capita income is $42,652. There are a total of 18,417 housing units with 81.0% owner occupied. Education includes 16.4% of residents that are high school graduates and 37.7% with a bachelor's degree or higher. The average temperature in Lincoln in the summer is 75 degrees, and in the winter 43 degrees.