Township · Illinois

Smithton Township, Illinois

Smithton Township, township, in St. Clair County, Illinois. Smithton Township had 4,018 residents on July 1, 2025 by the Census Bureau's estimate, down 3.6% since 2020; the 2020 Census counted 4,174 and the ACS 2020-2024 5-year estimates put it at 4,102 (±23). GEOID 1716370265.

Residents, July 2025 estimate

4,018

Census Bureau estimate (no margin published)
2020 Census count: 4,174 · ACS 2020-2024: 4,102 ±23

Median household income

$122,778

±$16,608 (90% margin)
Illinois: $83,390

Median home value

$258,800

±$16,489 (90% margin)
Illinois: $263,300

Median gross rent

$888

±$701 (90% margin)
Illinois: $1,274

Where is Smithton Township and what county is it in?

Smithton Township is a township in St. Clair County, Illinois. It covers 32.3 square miles of land, 129 residents per square mile in 2020.

One place lies inside Smithton Township: Smithton (village, 4,006 in 2020). Part of Freeburg (village) also lies in it.

Smithton Township is in the St. Louis, MO-IL metropolitan statistical area, which takes in 15 counties (Census Bureau delineation, July 2023).

Smithton Township (marked with a dot) in St. Clair County, Illinois. 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 Smithton Township, and is it growing?

The Census Bureau estimates that 4,018 people lived in Smithton Township on July 1, 2025, down 3.6% since 2020, a steeper fall than Illinois's (−0.8%). The 2020 Census counted 4,174 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 4,102 (±23).

  • July 2020→2021 −25 (4,134)
  • 2021→2022 −43 (4,091)
  • 2022→2023 −34 (4,057)
  • 2023→2024 −14 (4,043)
  • 2024→2025 −25 (4,018)
ACS 2020-2024 5-year estimates (counts) with the change from 2015-2019
MeasureSmithton TownshipSt. Clair CountyIllinoisChange since 2015-2019
Total population4,102±23253,69412,694,798−165
Households1,560±112100,8465,036,449no clear change
Average household size2.60±0.182.472.46no clear change
Housing units1,687±128115,6305,457,452no clear change

Smithton Township's population since 2000

From 3,392 in 2000 to 4,018 in 2025: up 18.5%. The 2000, 2010 and 2020 figures are census counts, each for Smithton 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 3,392
  • 2005 (estimate) 3,895
  • 2010 Census 4,275
  • 2015 (estimate) 4,292
  • 2020 Census 4,174
  • 2025 (estimate) 4,018

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 Smithton Township?

The median resident of Smithton Township is 41.6 years old; 25.5% are under 18 and 21.7% are 65 or older. The largest group is non-Hispanic white residents at 89.9%, then non-Hispanic residents of two or more races at 6.1%.

Age, origin, education and moves, ACS 2020-2024 5-year estimates. Race groups are non-Hispanic; Hispanic includes any race.
MeasureSmithton TownshipSt. Clair CountyIllinoisChange since 2015-2019
Median age41.6±3.439.939.0no clear change
Under 18 years25.5%±3.6 pts23.0%21.8%–
65 years and over21.7%±4.9 pts17.3%17.0%–
Male52.2%±3.9 pts48.5%49.4%–
Hispanic or Latino (any race)1.7%±1.7 pts5.1%18.8%–
White alone, not Hispanic89.9%±5.7 pts59.1%58.1%no clear change
Black or African American alone, not Hispanic0.2%±0.2 pts27.7%13.3%–
Asian alone, not Hispanic2.1%±1.5 pts1.6%5.9%–
American Indian and Alaska Native alone, not Hispanic0.0%±0.9 pts0.2%0.1%–
Native Hawaiian and Other Pacific Islander alone, not Hispanic0.0%±0.9 pts0.0%0.0%–
Two or more races, not Hispanic6.1%±4.3 pts5.8%3.4%–
Some other race alone, not Hispanic0.0%±0.9 pts0.5%0.4%–
Born outside the United States3.4%±3.1 pts3.3%14.7%–
Speak a language other than English at home (age 5+)2.9%±2.4 pts5.0%24.0%–
Civilian veterans (age 18+)11.8%±4.2 pts11.5%4.8%–
With a disability12.2%±4.1 pts15.2%12.1%–
No health insurance coverage2.2%±1.5 pts5.1%6.9%–
High school graduate or higher (age 25+)97.6%±1.7 pts93.5%90.5%–
Bachelor's degree or higher (age 25+)39.4%±8.0 pts31.8%37.8%no clear change
Graduate or professional degree (age 25+)15.6%±5.2 pts13.8%15.3%–
Lived in the same house a year earlier94.7%±3.0 pts88.3%88.9%–
Moved from another state in the past year0.8%±1.2 pts3.0%1.6%–

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 Smithton Township earn?

Half of Smithton Township's 1,560 households earn less than $122,778 a year (±$16,608), against $73,854 in St. Clair County and $83,390 in Illinois. In 2015-2019 the median was $92,675 in 2024 dollars, so it rose by $30,103 after inflation.

Income and poverty in 2024 dollars, ACS 2020-2024 5-year estimates; 2015-2019 dollars adjusted with the R-CPI-U-RS
MeasureSmithton TownshipSt. Clair CountyIllinoisChange since 2015-2019
Median household income$122,778±$16,608$73,854$83,390+$30,103
Mean household income$126,008±$11,483$96,049$115,638–
Per capita income$47,669±$3,862$38,942$46,406no clear change
People below the poverty line3.6%±3.3 pts13.6%11.8%–
Children under 18 below the poverty line2.1%±3.5 pts18.9%15.1%–
Households receiving SNAP6.8%±5.5 pts16.2%13.8%–
Households with a computer97.1%±2.9 pts94.2%95.2%–
Households with a broadband subscription97.0%±3.0 pts89.7%90.8%–

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 Smithton Township?

Owners occupy 92.0% of Smithton Township's occupied homes and renters 8.0%. The median owner-occupied home is valued at $258,800 by its owner (±$16,489).

Housing, ACS 2020-2024 5-year estimates. Home values are owners' own estimates.
MeasureSmithton TownshipSt. Clair CountyIllinoisChange since 2015-2019
Median home value (owner-occupied)$258,800±$16,489$180,300$263,300+$56,597
Median gross rent$888±$701$1,090$1,274–
Renters paying 35% or more of income on rent40.0%±39.9 pts39.8%39.0%–
Median monthly owner costs, with a mortgage$1,973±$172$1,645$1,987–
Owner-occupied homes92.0%±5.8 pts68.4%67.1%no clear change
Renter-occupied homes8.0%±5.8 pts31.6%32.9%–
Housing units1,687±128115,6305,457,452no clear change
Homeowner vacancy rate2.1%±1.8 pts1.1%1.0%–
Rental vacancy rate0.0%±25.5 pts4.7%5.0%–
Single-family detached homes87.0%±5.2 pts72.1%58.2%–
Mobile homes6.8%±4.7 pts4.4%2.3%–
Built 2020 or later6.0%±4.7 pts0.9%0.7%–
Built 2010 to 20195.1%±4.4 pts7.3%5.0%–
Built 1939 or earlier10.3%±7.0 pts13.5%20.2%–
Households with no vehicle1.2%±2.0 pts7.5%11.0%–

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 Smithton Township work and get to work?

77.1% of Smithton Township's workers drive alone and 16.5% work from home. The average trip to work takes 26.3 minutes.

Work and commuting, ACS 2020-2024 5-year estimates (workers 16 and over)
MeasureSmithton TownshipSt. Clair CountyIllinoisChange since 2015-2019
In the labor force (age 16+)64.7%±6.9 pts63.4%65.0%–
Unemployment rate4.9%±3.4 pts6.0%5.8%–
Drove alone to work77.1%±6.8 pts75.4%65.9%–
Carpooled6.4%±4.3 pts8.1%7.8%–
Public transportation0.0%±1.9 pts1.6%5.8%–
Walked0.0%±1.9 pts1.5%2.8%–
Worked from home16.5%±6.1 pts12.4%15.9%–
Mean travel time to work26.3 min±2.124.0 min27.8 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 Smithton Township?

1 census tract lies mostly in Smithton Township, and 3 more reach into it (2020 census blocks).

Census tracts in Smithton Township, ACS 2020-2024 5-year estimates
TractResidents, 2020-2024Median household incomeMedian home valueShare of tract in Smithton Township
Tract 5039.06St. Clair County5,211 $107,321 $248,00062%
Tract 5039.03St. Clair County4,092 $162,841 $352,4008%
Tract 5039.05St. Clair County2,920 $92,344 $237,60010%
Tract 5033.04St. Clair County6,619 $66,053 $179,5002%

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 Smithton Township) · Census block assignment files

How does Smithton Township compare with other places in Illinois?

By the Census Bureau's July 2025 estimates, Smithton Township is the 2,794th-most populous of the 16,079 U.S. towns and townships that have one and the 276th-most populous of 1,407 in Illinois.

Smithton Township ranks 137th of 1,380 places in Illinois with 1,000 or more residents and a reliable estimate, by median household income.

Smithton Township's rank in Illinois (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 estimate276th1,407
Growth 2020-2025 (PEP)1,138th1,347
Residents per square mile953rd1,383
Median household income137th1,380
Per capita income320th1,383
Median home value350th1,379
Bachelor's degree or higher272nd1,369
Median age627th1,383
Owner-occupied share146th1,382
Work from home242nd1,015
Travel time to work617th1,382

Smithton Township's figures with every place in Illinois (CSV)

Every place in Illinois, sortable · Compare Smithton 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 Smithton Township?

28 of the 57 figures for Smithton 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 Smithton 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.