| Official Name: | South Dennis, Massachusetts |
| Settlement Type: | Census-designated place |
| Mapsize: | 260px |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Massachusetts |
| Subdivision Type2: | County |
| Subdivision Name2: | Barnstable |
| Subdivision Type3: | Town |
| Subdivision Name3: | Dennis |
| Area Footnotes: | [1] |
| Area Total Km2: | 12.30 |
| Area Land Km2: | 11.79 |
| Area Water Km2: | 0.52 |
| Area Total Sq Mi: | 4.75 |
| Area Land Sq Mi: | 4.55 |
| Area Water Sq Mi: | 0.20 |
| Population As Of: | 2020 |
| Population Total: | 3899 |
| Population Density Km2: | 330.84 |
| Population Density Sq Mi: | 856.92 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation M: | 10 |
| Elevation Ft: | 33 |
| Coordinates: | 41.7058°N -70.1625°W |
| Postal Code Type: | ZIP code |
| Postal Code: | 02660 |
| Area Code: | 508 |
| Blank Name: | FIPS code |
| Blank Info: | 25-63655 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 0615880 |
| Unit Pref: | Imperial |
South Dennis is a census-designated place (CDP) in the town of Dennis in Barnstable County, Massachusetts, United States. The population was 3,643 at the 2010 census,[2] the largest of the five CDPs in Dennis.
South Dennis is located on Cape Cod, in the center of the town of Dennis at .[3] It is bordered by the town of Brewster to the northeast, the town of Harwich to the southeast, the CDPs of Dennis Port to the south and West Dennis to the southwest, the town of Yarmouth to the west, and the CDPs of Dennis and East Dennis to the north.
According to the United States Census Bureau, the South Dennis CDP has a total area of 12.3sqkm, of which 11.8sqkm is land, and 0.5sqkm (4.19%) is water.[2]
See also: List of Massachusetts locations by per capita income. As of the census[4] of 2000, 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.
N. H. Wixon Innovation School (grades 4–5) is a public school in South Dennis. The school was named after prominent Dennisport fisherman Nathaniel H. Wixon, a descendant of more than 15 of the original Mayflower Pilgrims.