2020 census As of the
2020 census, South Dennis had a population of 3,899. The median age was 55.6 years. 14.3% of residents were under the age of 18 and 33.1% of residents were 65 years of age or older. For every 100 females, there were 91.0 males, and for every 100 females age 18 and over, there were 87.5 males age 18 and over. 100.0% of residents lived in urban areas, while 0.0% lived in rural areas. There were 1,821 households in South Dennis, of which 17.8% had children under the age of 18 living in them. Of all households, 42.8% were married-couple households, 17.6% were households with a male householder and no spouse or partner present, and 33.2% were households with a female householder and no spouse or partner present. About 35.1% of all households were made up of individuals, and 19.3% had someone living alone who was 65 years of age or older., there were 3,679 people, 1,681 households, and 1,059 families residing in the CDP. The
population density was 312.2/km (808.3/mi). There were 2,468 housing units at an average density of 209.4/km (542.3/mi). The racial makeup of the CDP was 95.41%
White, 1.01%
African American, 0.60%
Native American, 0.35%
Asian, 0.90% from
other races, and 1.74% from two or more races.
Hispanic or
Latino of any race were 1.30% of the population. There were 1,681 households, out of which 23.7% had children under the age of 18 living with them, 48.7% were
married couples living together, 10.9% had a female householder with no husband present, and 37.0% were non-families. Of all households, 31.4% were made up of individuals, and 16.0% had someone living alone who was 65 years of age or older. The average household size was 2.19 and the average family size was 2.74. In the CDP, the population was spread out, with 20.3% under the age of 18, 4.2% from 18 to 24, 24.8% from 25 to 44, 26.1% from 45 to 64, and 24.6% who were 65 years of age or older. The median age was 46 years. For every 100 females, there were 83.4 males. For every 100 females age 18 and over, there were 78.8 males. The median income for a household in the CDP was $40,330, and the median income for a family was $47,935. Males had a median income of $35,026 versus $26,818 for females. The
per capita income for the CDP was $22,974. About 2.0% of families and 3.2% of the population were below the
poverty line, including 0.7% of those under age 18 and 3.7% of those age 65 or over. ==Education==