Township · Pennsylvania

St. Clair Township, Pennsylvania

St. Clair Township, township, in Westmoreland County, Pennsylvania. St. Clair Township had 1,302 residents on July 1, 2025 by the Census Bureau's estimate, down 2.9% since 2020; the 2020 Census counted 1,340 and the ACS 2020-2024 5-year estimates put it at 1,247 (±180). GEOID 4212967240.

Residents, July 2025 estimate

1,302

Census Bureau estimate (no margin published)
2020 Census count: 1,340 · ACS 2020-2024: 1,247 ±180

Median household income

$55,000

±$15,867 (90% margin)
Pennsylvania: $77,971

Median home value

$140,700

±$18,996 (90% margin)
Pennsylvania: $254,500

Median gross rent

$758

±$193 (90% margin)
Pennsylvania: $1,209

Where is St. Clair Township and what county is it in?

St. Clair Township is a township in Westmoreland County, Pennsylvania. It covers 28.6 square miles of land, 47 residents per square mile in 2020.

St. Clair Township is in the Pittsburgh, PA metropolitan statistical area, which takes in 8 counties (Census Bureau delineation, July 2023).

St. Clair Township (marked with a dot) in Westmoreland County, Pennsylvania. Boundaries: Census Bureau 2024.

Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files

How many people live in St. Clair Township, and is it growing?

The Census Bureau estimates that 1,302 people lived in St. Clair Township on July 1, 2025, down 2.9% since 2020, while Pennsylvania grew 0.4%. The 2020 Census counted 1,340 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 1,247 (±180).

  • July 2020→2021 −7 (1,332)
  • 2021→2022 −12 (1,320)
  • 2022→2023 −6 (1,314)
  • 2023→2024 −5 (1,309)
  • 2024→2025 −7 (1,302)
ACS 2020-2024 5-year estimates (counts) with the change from 2015-2019
MeasureSt. Clair TownshipWestmoreland CountyPennsylvaniaChange since 2015-2019
Total population1,247±180352,50013,018,639no clear change
Households524±62154,9795,274,853no clear change
Average household size2.38±0.232.232.39no clear change
Housing units613±65168,8125,806,452no clear change

St. Clair Township's population since 2000

From 1,398 in 2000 to 1,302 in 2025: down 6.9%. The 2000, 2010 and 2020 figures are census counts, each for St. Clair Township 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.

  • 2000 Census 1,398
  • 2005 (estimate) 1,450
  • 2010 Census 1,518
  • 2015 (estimate) 1,475
  • 2020 Census 1,340
  • 2025 (estimate) 1,302

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 St. Clair Township?

The median resident of St. Clair Township is 47.8 years old; 21.6% are under 18 and 21.4% are 65 or older. The largest group is non-Hispanic white residents at 97.2%, then non-Hispanic residents of two or more races at 1.4%.

Age, origin, education and moves, ACS 2020-2024 5-year estimates. Race groups are non-Hispanic; Hispanic includes any race.
MeasureSt. Clair TownshipWestmoreland CountyPennsylvaniaChange since 2015-2019
Median age47.8±6.547.240.9no clear change
Under 18 years21.6%±5.8 pts18.2%20.4%–
65 years and over21.4%±4.9 pts24.3%19.5%–
Male56.0%±4.6 pts49.4%49.3%–
Hispanic or Latino (any race)1.0%±1.2 pts1.6%8.7%–
White alone, not Hispanic97.2%±1.8 pts91.4%73.0%−2.4 pts
Black or African American alone, not Hispanic0.5%±0.5 pts2.5%10.3%–
Asian alone, not Hispanic0.0%±2.6 pts1.0%3.8%–
American Indian and Alaska Native alone, not Hispanic0.0%±2.6 pts0.0%0.1%–
Native Hawaiian and Other Pacific Islander alone, not Hispanic0.0%±2.6 pts0.0%0.0%–
Two or more races, not Hispanic1.4%±1.2 pts3.3%3.6%–
Some other race alone, not Hispanic0.0%±2.6 pts0.2%0.5%–
Born outside the United States0.0%±2.6 pts1.9%7.7%–
Speak a language other than English at home (age 5+)0.3%±0.4 pts2.8%12.4%–
Civilian veterans (age 18+)7.1%±2.7 pts7.3%6.1%–
With a disability19.6%±4.5 pts15.1%14.4%–
No health insurance coverage3.4%±2.8 pts3.0%5.6%–
High school graduate or higher (age 25+)95.6%±2.3 pts95.5%92.1%–
Bachelor's degree or higher (age 25+)17.4%±4.7 pts32.8%35.2%+6.1 pts
Graduate or professional degree (age 25+)7.5%±4.0 pts11.8%14.3%–
Lived in the same house a year earlier94.7%±2.8 pts92.3%89.3%–
Moved from another state in the past year0.0%±2.6 pts1.0%1.9%–

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 St. Clair Township earn?

Half of St. Clair Township's 524 households earn less than $55,000 a year (±$15,867), against $74,109 in Westmoreland County and $77,971 in Pennsylvania. In 2015-2019 it was $55,535 in 2024 dollars; the margins of error cannot tell the two periods apart. 16.6% of residents live below the poverty line.

Income and poverty in 2024 dollars, ACS 2020-2024 5-year estimates; 2015-2019 dollars adjusted with the R-CPI-U-RS
MeasureSt. Clair TownshipWestmoreland CountyPennsylvaniaChange since 2015-2019
Median household income$55,000±$15,867$74,109$77,971no clear change
Mean household income$71,645±$8,786$97,695$107,538–
Per capita income$30,691±$4,434$43,509$44,355no clear change
People below the poverty line16.6%±6.4 pts10.3%11.7%no clear change
Children under 18 below the poverty line18.1%±11.8 pts14.1%15.6%no clear change
Households receiving SNAP25.0%±7.3 pts13.9%14.4%–
Households with a computer90.8%±4.1 pts92.3%93.8%–
Households with a broadband subscription84.9%±6.1 pts88.5%89.7%–

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 St. Clair Township?

Owners occupy 78.6% of St. Clair Township's occupied homes and renters 21.4%. The median owner-occupied home is valued at $140,700 by its owner (±$18,996). The median renter pays $758 a month including utilities.

Housing, ACS 2020-2024 5-year estimates. Home values are owners' own estimates.
MeasureSt. Clair TownshipWestmoreland CountyPennsylvaniaChange since 2015-2019
Median home value (owner-occupied)$140,700±$18,996$203,500$254,500no clear change
Median gross rent$758±$193$879$1,209no clear change
Renters paying 35% or more of income on rent27.6%±22.7 pts32.7%39.5%–
Median monthly owner costs, with a mortgage$1,289±$110$1,452$1,762–
Owner-occupied homes78.6%±8.2 pts78.4%69.3%no clear change
Renter-occupied homes21.4%±8.2 pts21.6%30.7%–
Housing units613±65168,8125,806,452no clear change
Homeowner vacancy rate2.8%±3.7 pts0.6%0.8%–
Rental vacancy rate6.7%±10.1 pts3.9%4.9%–
Single-family detached homes72.9%±6.6 pts76.9%56.6%–
Mobile homes14.7%±6.1 pts5.1%3.5%–
Built 2020 or later0.0%±5.2 pts0.7%1.0%–
Built 2010 to 20191.8%±1.5 pts3.7%5.1%–
Built 1939 or earlier6.5%±2.5 pts19.8%25.0%–
Households with no vehicle5.3%±3.4 pts6.2%10.4%–

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 St. Clair Township building?

Builders took permits for 0 new housing units in St. Clair Township in 2025 (0 in single-family houses), 0.0 per 1,000 residents against 2.0 across Pennsylvania.

  • 2019 0 units
  • 2020 0 units
  • 2021 0 units
  • 2022 0 units
  • 2023 0 units
  • 2024 0 units
  • 2025 0 units

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 St. Clair Township work and get to work?

89.0% of St. Clair Township's workers drive alone and 5.8% work from home. The average trip to work takes 31.7 minutes. The unemployment rate in 2020-2024 averaged 10.7%.

Work and commuting, ACS 2020-2024 5-year estimates (workers 16 and over)
MeasureSt. Clair TownshipWestmoreland CountyPennsylvaniaChange since 2015-2019
In the labor force (age 16+)52.3%±5.7 pts60.3%62.7%–
Unemployment rate10.7%±5.7 pts4.8%5.3%no clear change
Drove alone to work89.0%±4.6 pts77.2%68.2%–
Carpooled2.8%±2.9 pts6.6%7.5%–
Public transportation0.0%±6.8 pts0.5%3.6%–
Walked0.9%±1.1 pts1.6%3.3%–
Worked from home5.8%±3.3 pts13.3%15.6%no clear change
Mean travel time to work31.7 min±3.826.7 min26.3 minno 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 St. Clair Township?

No census tract lies mostly in St. Clair Township; 1 tract reaches into it (2020 census blocks).

Census tracts in St. Clair Township, ACS 2020-2024 5-year estimates
TractResidents, 2020-2024Median household incomeMedian home valueShare of tract in St. Clair Township
Tract 8083Westmoreland County4,929 $63,859 $127,70024%

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 St. Clair Township) · Census block assignment files

How does St. Clair Township compare with other places in Pennsylvania?

By the Census Bureau's July 2025 estimates, St. Clair Township is the 6,527th-most populous of the 16,079 U.S. towns and townships that have one and the 1,015th-most populous of 1,542 in Pennsylvania.

St. Clair Township ranks 1,869th of 2,136 places in Pennsylvania with 1,000 or more residents and a reliable estimate, by median household income.

St. Clair Township's rank in Pennsylvania (1 = highest): by population among the state's towns and townships with a 2025 estimate; by the other measures among places of 1,000+ residents with a reliable estimate
MeasureRankOf
Population, July 2025 estimate1,015th1,542
Growth 2020-2025 (PEP)1,455th1,764
Residents per square mile1,981st2,159
Median household income1,869th2,136
Per capita income1,833rd2,157
Median home value1,813th2,146
Median gross rent1,708th1,963
Poverty rate280th1,606
Bachelor's degree or higher1,713th2,129
Median age601st2,157
Owner-occupied share1,189th2,149
Work from home1,608th1,710
Travel time to work297th2,156

St. Clair Township's figures with every place in Pennsylvania (CSV)

Every place in Pennsylvania, sortable · Compare St. Clair Township 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 St. Clair Township?

19 of the 57 figures for St. Clair Township 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 St. Clair Township 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.