Town · New York
Town of Sempronius, New York
Sempronius (town), town, in Cayuga County, New York. Sempronius (town) had 891 residents on July 1, 2025 by the Census Bureau's estimate, up 5.4% since 2020; the 2020 Census counted 840 and the ACS 2020-2024 5-year estimates put it at 789 (±157). GEOID 3601166278.
Residents, July 2025 estimate
891
Census Bureau estimate (no margin published)
2020 Census count: 840 · ACS 2020-2024: 789 ±157
Median household income
$70,000
±$10,878 (90% margin)
New York: $85,974
Median home value
$154,200
±$14,491 (90% margin)
New York: $423,800
Median gross rent
$950
±$336 (90% margin)
New York: $1,621
Where is Sempronius (town) and what county is it in?
Sempronius (town) is a town in Cayuga County, New York. It covers 29.3 square miles of land, 29 residents per square mile in 2020.
Sempronius (town) is in the Auburn, NY micropolitan statistical area (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 Sempronius (town), and is it growing?
The Census Bureau estimates that 891 people lived in Sempronius (town) on July 1, 2025, up 5.4% since 2020, while New York shrank 1.0%. The 2020 Census counted 840 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 789 (±157).
| Measure | Sempronius (town) | Cayuga County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 789±157 | 75,102 | no clear change |
| Households | 302±46 | 31,524 | no clear change |
| Average household size | 2.61±0.31 | 2.26 | no clear change |
| Housing units | 475±70 | 36,829 | no clear change |
Sempronius (town)'s population since 2000
From 893 in 2000 to 891 in 2025: down 0.2%. The 2000, 2010 and 2020 figures are census counts, each for Sempronius (town) 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 Sempronius (town)?
The median resident of Sempronius (town) is 41.8 years old; 22.8% are under 18 and 19.6% are 65 or older. The largest group is non-Hispanic white residents at 97.5%, then non-Hispanic residents of two or more races at 1.8%.
| Measure | Sempronius (town) | Cayuga County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 41.8±5.7 | 43.8 | no clear change |
| Under 18 years | 22.8%±5.3 pts | 19.3% | – |
| 65 years and over | 19.6%±5.1 pts | 21.3% | – |
| Male | 53.9%±4.7 pts | 51.2% | – |
| Hispanic or Latino (any race) | 0.8%±1.3 pts | 3.6% | – |
| White alone, not Hispanic | 97.5%±1.9 pts | 86.9% | no clear change |
| Black or African American alone, not Hispanic | 0.0%±5.2 pts | 3.3% | – |
| Asian alone, not Hispanic | 0.0%±5.2 pts | 0.7% | – |
| American Indian and Alaska Native alone, not Hispanic | 0.0%±5.2 pts | 0.1% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0%±5.2 pts | 0.0% | – |
| Two or more races, not Hispanic | 1.8%±1.3 pts | 4.9% | – |
| Some other race alone, not Hispanic | 0.0%±5.2 pts | 0.5% | – |
| Born outside the United States | 0.9%±1.3 pts | 2.6% | – |
| Speak a language other than English at home (age 5+) | 0.0%±5.6 pts | 4.0% | – |
| Civilian veterans (age 18+) | 9.2%±4.0 pts | 6.9% | – |
| With a disability | 9.4%±3.5 pts | 14.3% | – |
| No health insurance coverage | 3.5%±2.2 pts | 4.5% | no clear change |
| High school graduate or higher (age 25+) | 83.9%±5.6 pts | 89.4% | – |
| Bachelor's degree or higher (age 25+) | 16.1%±5.5 pts | 24.6% | no clear change |
| Graduate or professional degree (age 25+) | 7.0%±3.2 pts | 11.3% | – |
| Lived in the same house a year earlier | 97.2%±2.0 pts | 89.8% | – |
| Moved from another state in the past year | 0.3%±0.6 pts | 1.1% | – |
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 Sempronius (town) earn?
Half of Sempronius (town)'s 302 households earn less than $70,000 a year (±$10,878), against $67,904 in Cayuga County and $85,974 in New York. In 2015-2019 it was $64,941 in 2024 dollars; the margins of error cannot tell the two periods apart. 10.6% of residents live below the poverty line.
| Measure | Sempronius (town) | Cayuga County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $70,000±$10,878 | $67,904 | no clear change |
| Mean household income | $97,639±$32,068 | $86,583 | – |
| Per capita income | $38,221±$10,186 | $36,905 | no clear change |
| People below the poverty line | 10.6%±5.0 pts | 13.5% | no clear change |
| Children under 18 below the poverty line | 7.2%±6.3 pts | 17.3% | – |
| Households receiving SNAP | 8.9%±5.0 pts | 14.8% | – |
| Households with a computer | 88.7%±5.0 pts | 93.8% | – |
| Households with a broadband subscription | 87.4%±5.6 pts | 89.1% | – |
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 Sempronius (town)?
Owners occupy 92.1% of Sempronius (town)'s occupied homes and renters 7.9%. The median owner-occupied home is valued at $154,200 by its owner (±$14,491). The median renter pays $950 a month including utilities.
| Measure | Sempronius (town) | Cayuga County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $154,200±$14,491 | $171,000 | no clear change |
| Median gross rent | $950±$336 | $942 | no clear change |
| Renters paying 35% or more of income on rent | 31.3%±22.0 pts | 39.6% | – |
| Median monthly owner costs, with a mortgage | $1,319±$153 | $1,539 | – |
| Owner-occupied homes | 92.1%±4.8 pts | 71.4% | no clear change |
| Renter-occupied homes | 7.9%±4.8 pts | 28.6% | – |
| Housing units | 475±70 | 36,829 | no clear change |
| Homeowner vacancy rate | 0.0%±11.7 pts | 1.1% | – |
| Rental vacancy rate | 0.0%±69.2 pts | 3.4% | – |
| Single-family detached homes | 66.1%±8.1 pts | 66.8% | – |
| Mobile homes | 33.9%±8.1 pts | 9.2% | – |
| Built 2020 or later | 1.7%±2.5 pts | 0.7% | – |
| Built 2010 to 2019 | 1.7%±1.5 pts | 3.9% | – |
| Built 1939 or earlier | 24.8%±6.6 pts | 36.6% | – |
| Households with no vehicle | 1.7%±1.8 pts | 9.1% | – |
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 many new homes is Sempronius (town) building?
Builders took permits for 8 new housing units in Sempronius (town) in 2025 (8 in single-family houses), 9.0 per 1,000 residents against 1.9 across New York.
Counts of units in permits a local office issued; not every permitted unit is built. A year marked with months was reported for part of the year.
Source: Building Permits Survey, annual place files 2019-2025, U.S. Census Bureau · Census Building Permits Survey
How do people in Sempronius (town) work and get to work?
87.6% of Sempronius (town)'s workers drive alone and 5.8% work from home. The average trip to work takes 29.3 minutes.
| Measure | Sempronius (town) | Cayuga County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 63.7%±8.8 pts | 58.1% | – |
| Unemployment rate | 3.0%±2.9 pts | 3.8% | – |
| Drove alone to work | 87.6%±5.6 pts | 78.8% | – |
| Carpooled | 5.8%±3.6 pts | 8.1% | – |
| Public transportation | 0.0%±10.6 pts | 0.3% | – |
| Walked | 0.8%±1.0 pts | 3.7% | – |
| Worked from home | 5.8%±3.6 pts | 7.7% | no clear change |
| Mean travel time to work | 29.3 min±5.6 | 22.8 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 Sempronius (town)?
No census tract lies mostly in Sempronius (town); 1 tract reaches into it (2020 census blocks).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 409Cayuga County | 3,480 | $69,011 |
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 Sempronius (town)) · Census block assignment files
How does Sempronius (town) compare with other places in New York?
By the Census Bureau's July 2025 estimates, Sempronius (town) is the 8,099th-most populous of the 16,079 U.S. towns and townships that have one and the 824th-most populous of 924 in New York.
Sempronius (town) is not ranked by income or the other survey measures: those rankings include places of 1,000 or more residents (2020 Census) with a reliable estimate.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 824th | 924 |
Sempronius (town)'s figures with every place in New York (CSV)
Every place in New York, sortable · Compare Sempronius (town) 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 Sempronius (town)?
20 of the 57 figures for Sempronius (town) 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 Sempronius (town) 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' school search.