Township · Illinois

Allens Grove Township, Illinois

Allens Grove Township, township, in Mason County, Illinois. Allens Grove Township had 434 residents on July 1, 2025 by the Census Bureau's estimate, down 5.2% since 2020; the 2020 Census counted 470 and the ACS 2020-2024 5-year estimates put it at 395 (±98). GEOID 1712500844.

Residents, July 2025 estimate

434

Census Bureau estimate (no margin published)
2020 Census count: 470 · ACS 2020-2024: 395 ±98

Median household income

$58,750

±$11,737 (90% margin)
Illinois: $83,390

Median home value

$94,300

±$26,438 (90% margin)
Illinois: $263,300

Median gross rent

not published


Illinois: $1,274

Where is Allens Grove Township and what county is it in?

Allens Grove Township is a township in Mason County, Illinois. It covers 35.7 square miles of land, 13 residents per square mile in 2020.

One place lies inside Allens Grove Township: San Jose (village, 479 in 2020).

Allens Grove Township (marked with a dot) in Mason 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 Allens Grove Township, and is it growing?

The Census Bureau estimates that 434 people lived in Allens Grove Township on July 1, 2025, down 5.2% since 2020, a steeper fall than Illinois's (−0.8%). The 2020 Census counted 470 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 395 (±98).

  • July 2020→2021 −8 (449)
  • 2021→2022 −4 (445)
  • 2022→2023 −6 (439)
  • 2023→2024 −3 (436)
  • 2024→2025 −2 (434)
ACS 2020-2024 5-year estimates (counts) with the change from 2015-2019
MeasureAllens Grove TownshipMason CountyIllinoisChange since 2015-2019
Total population395±9812,74512,694,798−321
Households172±415,7815,036,449−104
Average household size2.30±0.372.172.46no clear change
Housing units201±456,6225,457,452−133

Allens Grove Township's population since 2000

From 699 in 2000 to 434 in 2025: down 37.9%. The 2000, 2010 and 2020 figures are census counts, each for Allens Grove 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 699
  • 2005 (estimate) 645
  • 2010 Census 586
  • 2015 (estimate) 557
  • 2020 Census 470
  • 2025 (estimate) 434

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 Allens Grove Township?

The median resident of Allens Grove Township is 37.4 years old; 29.1% are under 18 and 15.4% are 65 or older. The largest group is non-Hispanic white residents at 82.8%, then non-Hispanic residents of two or more races at 10.4%.

Age, origin, education and moves, ACS 2020-2024 5-year estimates. Race groups are non-Hispanic; Hispanic includes any race.
MeasureAllens Grove TownshipMason CountyIllinoisChange since 2015-2019
Median age37.4±15.345.439.0no clear change
Under 18 years29.1%±8.3 pts20.8%21.8%–
65 years and over15.4%±7.0 pts23.1%17.0%–
Male41.0%±5.8 pts49.7%49.4%–
Hispanic or Latino (any race)6.8%±8.7 pts1.6%18.8%–
White alone, not Hispanic82.8%±9.3 pts94.2%58.1%no clear change
Black or African American alone, not Hispanic0.0%±9.1 pts0.5%13.3%–
Asian alone, not Hispanic0.0%±9.1 pts0.4%5.9%–
American Indian and Alaska Native alone, not Hispanic0.0%±9.1 pts0.2%0.1%–
Native Hawaiian and Other Pacific Islander alone, not Hispanic0.0%±9.1 pts0.0%0.0%–
Two or more races, not Hispanic10.4%±6.0 pts3.1%3.4%–
Some other race alone, not Hispanic0.0%±9.1 pts0.0%0.4%–
Born outside the United States0.0%±9.1 pts0.9%14.7%–
Speak a language other than English at home (age 5+)0.0%±9.7 pts2.2%24.0%–
Civilian veterans (age 18+)5.4%±4.2 pts8.3%4.8%–
With a disability9.6%±5.5 pts17.9%12.1%–
No health insurance coverage3.0%±3.2 pts3.9%6.9%–
High school graduate or higher (age 25+)91.0%±5.8 pts93.0%90.5%–
Bachelor's degree or higher (age 25+)8.6%±6.5 pts17.1%37.8%–
Graduate or professional degree (age 25+)4.1%±4.3 pts5.5%15.3%–
Lived in the same house a year earlier96.2%±4.8 pts92.6%88.9%–
Moved from another state in the past year0.0%±9.1 pts0.9%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 Allens Grove Township earn?

Half of Allens Grove Township's 172 households earn less than $58,750 a year (±$11,737), against $62,845 in Mason County and $83,390 in Illinois. In 2015-2019 it was $69,055 in 2024 dollars; the margins of error cannot tell the two periods apart. 19.0% 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
MeasureAllens Grove TownshipMason CountyIllinoisChange since 2015-2019
Median household income$58,750±$11,737$62,845$83,390no clear change
Mean household income$76,661±$14,851$78,083$115,638–
Per capita income$32,985±$5,682$34,815$46,406no clear change
People below the poverty line19.0%±10.1 pts14.8%11.8%no clear change
Children under 18 below the poverty line33.0%±19.1 pts19.6%15.1%–
Households receiving SNAP23.8%±12.2 pts15.5%13.8%–
Households with a computer100.0%±19.5 pts91.6%95.2%–
Households with a broadband subscription92.4%±8.7 pts87.0%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 Allens Grove Township?

Owners occupy 80.2% of Allens Grove Township's occupied homes and renters 19.8%. The median owner-occupied home is valued at $94,300 by its owner (±$26,438).

Housing, ACS 2020-2024 5-year estimates. Home values are owners' own estimates.
MeasureAllens Grove TownshipMason CountyIllinoisChange since 2015-2019
Median home value (owner-occupied)$94,300±$26,438$103,400$263,300no clear change
Renters paying 35% or more of income on rent55.2%±33.7 pts54.8%39.0%–
Median monthly owner costs, with a mortgage$1,115±$70$1,140$1,987–
Owner-occupied homes80.2%±12.0 pts81.8%67.1%no clear change
Renter-occupied homes19.8%±12.0 pts18.2%32.9%–
Housing units201±456,6225,457,452−133
Homeowner vacancy rate1.4%±2.3 pts1.1%1.0%–
Rental vacancy rate34.6%±32.8 pts4.0%5.0%–
Single-family detached homes89.1%±9.8 pts88.9%58.2%–
Mobile homes1.0%±1.8 pts4.2%2.3%–
Built 2020 or later0.0%±16.9 pts0.3%0.7%–
Built 2010 to 20190.5%±1.9 pts2.6%5.0%–
Built 1939 or earlier48.3%±12.3 pts29.1%20.2%–
Households with no vehicle7.6%±7.0 pts7.9%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 Allens Grove Township work and get to work?

90.3% of Allens Grove Township's workers drive alone. The average trip to work takes 33.9 minutes.

Work and commuting, ACS 2020-2024 5-year estimates (workers 16 and over)
MeasureAllens Grove TownshipMason CountyIllinoisChange since 2015-2019
In the labor force (age 16+)69.9%±9.1 pts54.3%65.0%–
Unemployment rate6.1%±4.3 pts4.9%5.8%–
Drove alone to work90.3%±10.4 pts82.8%65.9%–
Carpooled0.0%±18.2 pts4.5%7.8%–
Public transportation0.0%±18.2 pts0.3%5.8%–
Walked0.0%±18.2 pts2.2%2.8%–
Worked from home7.6%±10.1 pts8.2%15.9%–
Mean travel time to work33.9 min±4.930.4 min27.8 min+6.8 min

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 Allens Grove Township?

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

Census tracts in Allens Grove Township, ACS 2020-2024 5-year estimates
TractResidents, 2020-2024Median household incomeMedian home valueShare of tract in Allens Grove Township
Tract 9567Mason County1,748 $61,333 $109,70027%

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 Allens Grove Township) · Census block assignment files

How does Allens Grove Township compare with other places in Illinois?

By the Census Bureau's July 2025 estimates, Allens Grove Township is the 10,479th-most populous of the 16,079 U.S. towns and townships that have one and the 1,041st-most populous of 1,407 in Illinois.

Allens Grove Township 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.

Allens Grove 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 estimate1,041st1,407

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

Every place in Illinois, sortable · Compare Allens Grove 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 Allens Grove Township?

24 of the 56 figures for Allens Grove 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 Allens Grove 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.