Town · South Carolina
Duncan, South Carolina
Duncan, town, in Spartanburg County, South Carolina. Duncan had 4,675 residents on July 1, 2025 by the Census Bureau's estimate, up 16.2% since 2020; the 2020 Census counted 4,041 and the ACS 2020-2024 5-year estimates put it at 4,310 (±21). GEOID 4521265.
Residents, July 2025 estimate
4,675
Census Bureau estimate (no margin published)
2020 Census count: 4,041 · ACS 2020-2024: 4,310 ±21
Median household income
$52,500
±$29,327 (90% margin)
South Carolina: $69,324
Median home value
$211,400
±$25,258 (90% margin)
South Carolina: $259,000
Median gross rent
$1,032
±$180 (90% margin)
South Carolina: $1,180
Where is Duncan and what county is it in?
Duncan is a town in Spartanburg County, South Carolina. It covers 6.6 square miles of land, 610 residents per square mile in 2020.
Duncan is in the Spartanburg, SC metropolitan statistical area, which takes in 2 counties (Census Bureau delineation, July 2023).
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Duncan, and is it growing?
The Census Bureau estimates that 4,675 people lived in Duncan on July 1, 2025, up 16.2% since 2020, faster than South Carolina (+8.8%). The 2020 Census counted 4,041 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 4,310 (±21).
| Measure | Duncan | Spartanburg County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 4,310 ±21 | 347,852 | +837 |
| Households | 1,868 ±254 | 131,672 | +545 |
| Average household size | 2.29 ±0.31 | 2.58 | no clear change |
| Housing units | 2,054 ±285 | 144,170 | +627 |
Duncan's population since 2000
From 2,870 in 2000 to 4,675 in 2025: up 62.9%. The 2000, 2010 and 2020 figures are census counts, each for Duncan as it was drawn that year: a place that annexed land, or a community that has since incorporated, covered a different area then. The 2005 figure is the Census Bureau's intercensal estimate, revised to fit the 2000 and 2010 counts and drawn on 2010 boundaries; 2015 and 2025 are July 1 estimates made from the census before them.
Source: The 2000, 2010 and 2020 Census counts and the Census Bureau's population estimates (intercensal 2000-2010, Vintage 2020, Vintage 2025) · Census population estimates
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); Census PEP Vintage 2025 (SUB-EST2025, CO-EST2025); 2020 Census P.L. 94-171 · Check it at data.census.gov
Who lives in Duncan?
The median resident of Duncan is 34.4 years old; 23.8% are under 18 and 10.0% are 65 or older. The largest group is non-Hispanic white residents at 54.0%, then non-Hispanic Black residents at 32.6%.
| Measure | Duncan | Spartanburg County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 34.4 ±2.6 | 37.8 | +4.8 |
| Under 18 years | 23.8% ±5.6 pts | 23.4% | – |
| 65 years and over | 10.0% ±5.3 pts | 16.3% | – |
| Male | 55.1% ±6.5 pts | 48.8% | – |
| Hispanic or Latino (any race) | 10.3% ±7.7 pts | 9.3% | – |
| White alone, not Hispanic | 54.0% ±12.2 pts | 65.3% | no clear change |
| Black or African American alone, not Hispanic | 32.6% ±13.4 pts | 19.3% | no clear change |
| Asian alone, not Hispanic | 0.0% ±1.0 pts | 2.3% | – |
| American Indian and Alaska Native alone, not Hispanic | 0.0% ±1.0 pts | 0.1% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±1.0 pts | 0.0% | – |
| Two or more races, not Hispanic | 1.5% ±1.3 pts | 3.3% | – |
| Some other race alone, not Hispanic | 1.6% ±2.6 pts | 0.4% | – |
| Born outside the United States | 8.7% ±7.8 pts | 8.7% | – |
| Speak a language other than English at home (age 5+) | 13.7% ±13.0 pts | 13.3% | – |
| Civilian veterans (age 18+) | 4.2% ±5.0 pts | 6.6% | – |
| With a disability | 14.9% ±7.4 pts | 15.1% | – |
| No health insurance coverage | 12.9% ±7.1 pts | 10.7% | no clear change |
| High school graduate or higher (age 25+) | 89.3% ±6.1 pts | 88.4% | – |
| Bachelor's degree or higher (age 25+) | 29.5% ±10.5 pts | 25.1% | no clear change |
| Graduate or professional degree (age 25+) | 7.9% ±5.6 pts | 9.6% | – |
| Lived in the same house a year earlier | 90.9% ±5.5 pts | 86.9% | – |
| Moved from another state in the past year | 0.2% ±0.1 pts | 2.9% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profiles DP02, DP05) · Check it at data.census.gov
What do households in Duncan earn?
Half of Duncan's 1,868 households earn less than $52,500 a year (±$29,327), against $66,234 in Spartanburg County and $69,324 in South Carolina. In 2015-2019 it was $55,426 in 2024 dollars; the margins of error cannot tell the two periods apart.
| Measure | Duncan | Spartanburg County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $52,500 ±$29,327 | $66,234 | no clear change |
| Mean household income | $84,142 ±$26,329 | $87,462 | – |
| Per capita income | $37,672 ±$13,052 | $34,071 | no clear change |
| People below the poverty line | 12.4% ±12.1 pts | 14.5% | – |
| Children under 18 below the poverty line | 21.1% ±21.9 pts | 19.1% | – |
| Households receiving SNAP | 14.5% ±11.2 pts | 10.9% | – |
| Households with a computer | 98.2% ±1.9 pts | 94.3% | – |
| Households with a broadband subscription | 87.0% ±10.1 pts | 88.7% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What does housing cost in Duncan?
Owners occupy 56.7% of Duncan's occupied homes and renters 43.3%. The median owner-occupied home is valued at $211,400 by its owner (±$25,258). The median renter pays $1,032 a month including utilities, and 35.0% of renters pay 35% or more of their income on rent.
| Measure | Duncan | Spartanburg County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $211,400 ±$25,258 | $233,300 | +$61,748 |
| Median gross rent | $1,032 ±$180 | $1,084 | no clear change |
| Renters paying 35% or more of income on rent | 35.0% ±22.9 pts | 40.0% | no clear change |
| Median monthly owner costs, with a mortgage | $1,148 ±$128 | $1,401 | – |
| Owner-occupied homes | 56.7% ±12.3 pts | 73.0% | no clear change |
| Renter-occupied homes | 43.3% ±12.3 pts | 27.0% | – |
| Housing units | 2,054 ±285 | 144,170 | +627 |
| Homeowner vacancy rate | 0.0% ±4.2 pts | 0.5% | – |
| Rental vacancy rate | 17.9% ±15.8 pts | 7.1% | – |
| Single-family detached homes | 64.2% ±13.2 pts | 71.9% | – |
| Mobile homes | 7.1% ±4.5 pts | 12.2% | – |
| Built 2020 or later | 12.9% ±7.4 pts | 5.4% | – |
| Built 2010 to 2019 | 24.5% ±11.5 pts | 14.8% | – |
| Built 1939 or earlier | 6.0% ±7.1 pts | 5.5% | – |
| Households with no vehicle | 1.8% ±1.9 pts | 4.5% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP04) · Check it at data.census.gov
How do people in Duncan work and get to work?
86.5% of Duncan's workers drive alone. The average trip to work takes 28.1 minutes.
| Measure | Duncan | Spartanburg County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 72.8% ±7.7 pts | 62.1% | – |
| Unemployment rate | 5.4% ±4.7 pts | 4.3% | – |
| Drove alone to work | 86.5% ±8.0 pts | 79.1% | – |
| Carpooled | 12.1% ±7.5 pts | 10.0% | – |
| Public transportation | 0.0% ±2.1 pts | 0.1% | – |
| Walked | 0.0% ±2.1 pts | 0.7% | – |
| Worked from home | 1.4% ±2.2 pts | 8.9% | – |
| Mean travel time to work | 28.1 min ±5.7 | 25.2 min | no clear change |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What census tracts are in Duncan?
1 census tract lies mostly in Duncan, and 4 more reach into it (2020 census blocks).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 231.01Spartanburg County | 5,825 | $51,486 |
| Tract 230.04Spartanburg County | 8,852 | $76,152 |
| Tract 234.06Spartanburg County | 4,301 | $85,732 |
| Tract 232.02Spartanburg County | 5,233 | $80,037 |
| Tract 231.04Spartanburg County | 4,252 | $49,670 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 block assignment files (tract share = share of the tract's census blocks in Duncan) · Census block assignment files
How does Duncan compare with other places in South Carolina?
By the Census Bureau's July 2025 estimates, Duncan is the 5,089th-most populous of the 19,476 U.S. incorporated places that have one and the 69th-most populous of 271 in South Carolina.
Duncan ranks 138th of 248 places in South Carolina with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 69th | 271 |
| Growth 2020-2025 (PEP) | 22nd | 149 |
| Residents per square mile | 193rd | 261 |
| Median household income | 138th | 248 |
| Per capita income | 73rd | 259 |
| Median home value | 106th | 248 |
| Median gross rent | 114th | 235 |
| Bachelor's degree or higher | 82nd | 226 |
| Median age | 201st | 261 |
| Owner-occupied share | 180th | 258 |
| Travel time to work | 63rd | 261 |
Duncan's figures with every place in South Carolina (CSV)
Every place in South Carolina, sortable · Compare Duncan with other places
Source: PlainCities ranks computed from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) and PEP Vintage 2025 · How ranks are computed
How reliable are the figures for Duncan?
21 of the 57 figures for Duncan on this page carry a coefficient of variation over 40% and are marked with a ring: they come from a small sample, so read them as rough.
The American Community Survey samples about one household in eight over five years, so every figure is an estimate with a 90% margin of error (shown under each value). A ring marks an estimate whose coefficient of variation is over 40%. A change is called only when the gap between the two periods is larger than their combined 90% margin (the square root of the sum of the two squared margins), the Census Bureau's test. How to read a margin of error.
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026): margins of error as published · ACS technical documentation
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections
Not on this page: crime, weather and schools for Duncan are other agencies' records. Crime: the FBI's Crime Data Explorer · climate: NOAA's U.S. Climate Normals · schools: the National Center for Education Statistics' public schools in Duncan.