South Dennis, Massachusetts Demographics & Population 2026
During the 2020–2024 ACS period, South Dennis, Massachusetts had a total population of 3,135, the 154th largest community in Massachusetts, with a median household income of $88,411, which is 15% lower than the state average. The poverty rate is 3.0%.
Data vintage: U.S. Census Bureau ACS 2020–2024 5-Year Estimates · refreshed July 2026 · Methodology & source notes
Key Takeaways
- An exceptionally low poverty rate of 3.0% — among the lowest in Massachusetts.
South Dennis Quick Facts
How South Dennis Changed
Change from the 2019–2023 ACS period to 2020–2024. These are rolling five-year estimates, not year-over-year measurements.
| Metric | 2019–2023 | 2020–2024 | Change |
|---|---|---|---|
| Population | 3,190 | 3,135 | -1.7% |
| Median household income | $86,500 | $88,411 | +2.2% |
| Median home value | $454,400 | $495,700 | +9.1% |
How South Dennis Compares
Median Household Income
Median Home Value
Economy & Housing
Household Income Distribution
Detailed income brackets
Employment
Housing Overview
People & Demographics
Age Distribution
Race & Ethnicity
Diversity Index
A less diverse community where one racial or ethnic group represents a large majority.
State average: 53 | National average: 61
Education
Educational Attainment (Adults 25+)
South Dennis Rankings in Massachusetts
Explore Massachusetts Rankings
Other Cities in Barnstable County
| City | Population | Median Income | Poverty | Home Value |
|---|---|---|---|---|
| Barnstable Town | 49,568 | $91,982 | 7.4% | $602,500 |
| South Yarmouth | 11,552 | $82,188 | 11.6% | $541,700 |
| East Falmouth | 6,245 | $81,464 | 8.6% | $593,000 |
| West Yarmouth | 6,194 | $65,841 | 9.1% | $494,600 |
| Yarmouth Port | 5,961 | $110,304 | 7.7% | $604,900 |
| East Harwich | 5,654 | $111,508 | 1.7% | $638,900 |
| Sagamore | 4,072 | $108,315 | 2.5% | $575,700 |
| Falmouth | 3,954 | $68,227 | 21.8% | $837,900 |
| Northwest Harwich | 3,932 | $107,730 | 7.5% | $665,100 |
| East Sandwich | 3,864 | $115,000 | 11.5% | $689,000 |
Cities Similar to South Dennis
These cities in the same state have comparable population and economic profiles.
| City | Population | Median Income | Home Value | Bachelor's+ | Poverty |
|---|---|---|---|---|---|
| Ayer | 3,098 | $74,878 | $444,600 | 37.7% | 6.9% |
| East Dennis | 3,062 | $103,654 | $694,000 | 43.2% | 4.8% |
| Buzzards Bay | 2,909 | $94,388 | $454,500 | 29.6% | 7.3% |
| Monument Beach | 3,277 | $77,167 | $559,900 | 45.7% | 6.2% |
| Upton | 3,234 | $110,900 | $476,300 | 39.4% | 3.4% |
Population Overview
South Dennis is a small community located in Massachusetts, within Barnstable County. The total population is 3,135. It ranks as the 154th most populous out of 248 Census-designated places in Massachusetts.
Age Demographics
The median age in South Dennis is 57.6 years. This is 44% higher than the state median of 40.0 years. Only 10.4% of residents are under 18, indicating fewer families with children. 16.6% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.
Economy, Income & Housing
The median household income in South Dennis is $88,411. This is 15% lower than the state median of $103,960. It is also 10% higher than the national median of $80,734. The poverty rate stands at 3.0%. This is 70% lower than the state poverty rate of 10.0%. This exceptionally low poverty rate indicates strong economic prosperity across the community. The unemployment rate is 3.8%. This is 27% lower than the state rate of 5.1%. The median home value is $495,700. Housing costs are 12% lower than the state median of $562,100. The home-value-to-income ratio is 5.6x. 82.7% of occupied housing units are owner-occupied. This homeownership rate is 32% higher than the state average of 62.5%.
Race & Ethnicity
South Dennis has a predominantly White (non-Hispanic) population, comprising 91.4% of all residents. Black or African American residents account for 4.7%. The Hispanic or Latino population (0.4%) is well below the state average of 13.3%. The Asian population (0.5%) is well below the state average of 7.2%.
Education
43.3% of residents aged 25 and older hold a bachelor's degree or higher. This is 8% lower than the state rate of 47.3%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 97.5%.
Data Sources & Methodology
All demographic data for South Dennis, Massachusetts is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against Massachusetts state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 248 Census-designated places in Massachusetts. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.
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Frequently Asked Questions
What is the population of South Dennis, Massachusetts?
South Dennis, Massachusetts has a population of 3,135 according to the most recent U.S. Census ACS 5-Year Estimates.
What is the median household income in South Dennis, MA?
The median household income in South Dennis is $88,411, which is 10% higher than the national median of $80,734.
What is the poverty rate in South Dennis, MA?
The poverty rate in South Dennis is 3.0%. This means approximately 92 residents live below the federal poverty line.
What is the racial makeup of South Dennis, Massachusetts?
South Dennis's population is 91.4% White, 4.7% Black, 0.4% Hispanic/Latino, and 0.5% Asian.
What is the median home value in South Dennis, MA?
The median home value in South Dennis is $495,700. The home-value-to-income ratio is 5.6x.
How educated is South Dennis, Massachusetts?
43.3% of adults (25+) in South Dennis hold a bachelor's degree or higher, and 14.3% hold a graduate or professional degree.