The population of Accomac was spread out. 14.8% were under the age of 18, 11.0% were from 18 to 24, 30.7% from 25 to 44, 24.1% from 45 to 64, and 19.4% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 131.8 males. For every 100 females age 18 and over, there were 136.5 males.