Township · Illinois

Marengo Township, Illinois

Marengo Township, township, in McHenry County, Illinois. Marengo Township had 7,354 residents on July 1, 2025 by the Census Bureau's estimate, up 1.6% since 2020; the 2020 Census counted 7,202 and the ACS 2020-2024 5-year estimates put it at 7,253 (±25). GEOID 1711146799.

Residents, July 2025 estimate

7,354

Census Bureau estimate (no margin published)
2020 Census count: 7,202 · ACS 2020-2024: 7,253 ±25

Median household income

$74,172

±$22,805 (90% margin)
Illinois: $83,390

Median home value

$234,900

±$10,797 (90% margin)
Illinois: $263,300

Median gross rent

$1,152

±$210 (90% margin)
Illinois: $1,274

Where is Marengo Township and what county is it in?

Marengo Township is a township in McHenry County, Illinois. It covers 35.9 square miles of land, 200 residents per square mile in 2020.

One place lies inside Marengo Township: Marengo (city, 7,568 in 2020).

Marengo Township is in the Chicago-Naperville-Elgin, IL-IN metropolitan statistical area, which takes in 13 counties (Census Bureau delineation, July 2023).

Marengo Township (marked with a dot) in McHenry 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 Marengo Township, and is it growing?

The Census Bureau estimates that 7,354 people lived in Marengo Township on July 1, 2025, up 1.6% since 2020, while Illinois shrank 0.8%. The 2020 Census counted 7,202 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 7,253 (±25).

  • July 2020→2021 +26 (7,249)
  • 2021→2022 −23 (7,226)
  • 2022→2023 +41 (7,267)
  • 2023→2024 +57 (7,324)
  • 2024→2025 +30 (7,354)
ACS 2020-2024 5-year estimates (counts) with the change from 2015-2019
MeasureMarengo TownshipMcHenry CountyIllinoisChange since 2015-2019
Total population7,253±25312,59112,694,798−111
Households2,899±283117,5945,036,449no clear change
Average household size2.48±0.242.642.46no clear change
Housing units2,968±286121,3295,457,452no clear change

Marengo Township's population since 2000

From 7,239 in 2000 to 7,354 in 2025: up 1.6%. The 2000, 2010 and 2020 figures are census counts, each for Marengo 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 7,239
  • 2005 (estimate) 7,657
  • 2010 Census 7,564
  • 2015 (estimate) 7,409
  • 2020 Census 7,202
  • 2025 (estimate) 7,354

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 Marengo Township?

The median resident of Marengo Township is 32.7 years old; 24.2% are under 18 and 19.4% are 65 or older. The largest group is non-Hispanic white residents at 85.2%, then Hispanic or Latino residents (of any race) at 10.0%. 3.4% of residents were born outside the United States.

Age, origin, education and moves, ACS 2020-2024 5-year estimates. Race groups are non-Hispanic; Hispanic includes any race.
MeasureMarengo TownshipMcHenry CountyIllinoisChange since 2015-2019
Median age32.7±5.840.739.0−10.3
Under 18 years24.2%±4.7 pts22.7%21.8%–
65 years and over19.4%±3.8 pts16.5%17.0%–
Male53.5%±4.4 pts50.1%49.4%–
Hispanic or Latino (any race)10.0%±6.3 pts16.1%18.8%−8.3 pts
White alone, not Hispanic85.2%±6.9 pts76.1%58.1%no clear change
Black or African American alone, not Hispanic0.7%±0.7 pts1.4%13.3%–
Asian alone, not Hispanic0.1%±0.2 pts3.0%5.9%–
American Indian and Alaska Native alone, not Hispanic0.0%±0.5 pts0.0%0.1%–
Native Hawaiian and Other Pacific Islander alone, not Hispanic0.0%±0.5 pts0.0%0.0%–
Two or more races, not Hispanic4.1%±2.7 pts3.2%3.4%–
Some other race alone, not Hispanic0.0%±0.5 pts0.2%0.4%–
Born outside the United States3.4%±1.9 pts9.9%14.7%−5.1 pts
Speak a language other than English at home (age 5+)9.9%±5.4 pts16.1%24.0%–
Civilian veterans (age 18+)4.9%±2.6 pts5.6%4.8%–
With a disability15.3%±5.0 pts10.1%12.1%–
No health insurance coverage3.9%±2.0 pts4.5%6.9%no clear change
High school graduate or higher (age 25+)95.9%±2.4 pts93.7%90.5%–
Bachelor's degree or higher (age 25+)19.1%±5.3 pts35.2%37.8%no clear change
Graduate or professional degree (age 25+)4.4%±2.4 pts12.0%15.3%–
Lived in the same house a year earlier78.7%±7.8 pts91.4%88.9%–
Moved from another state in the past year1.3%±1.3 pts1.0%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 Marengo Township earn?

Half of Marengo Township's 2,899 households earn less than $74,172 a year (±$22,805), against $104,802 in McHenry County and $83,390 in Illinois. In 2015-2019 it was $77,503 in 2024 dollars; the margins of error cannot tell the two periods apart. 13.2% 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
MeasureMarengo TownshipMcHenry CountyIllinoisChange since 2015-2019
Median household income$74,172±$22,805$104,802$83,390no clear change
Mean household income$93,280±$11,712$130,520$115,638–
Per capita income$38,127±$3,978$49,388$46,406no clear change
People below the poverty line13.2%±6.1 pts6.2%11.8%no clear change
Children under 18 below the poverty line18.4%±12.8 pts8.2%15.1%–
Households receiving SNAP19.2%±5.8 pts7.4%13.8%–
Households with a computer94.7%±4.2 pts97.7%95.2%–
Households with a broadband subscription95.7%±3.0 pts95.4%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 Marengo Township?

Owners occupy 62.1% of Marengo Township's occupied homes and renters 37.9%. The median owner-occupied home is valued at $234,900 by its owner (±$10,797). The median renter pays $1,152 a month including utilities, and 53.5% of renters pay 35% or more of their income on rent.

Housing, ACS 2020-2024 5-year estimates. Home values are owners' own estimates.
MeasureMarengo TownshipMcHenry CountyIllinoisChange since 2015-2019
Median home value (owner-occupied)$234,900±$10,797$308,100$263,300+$39,220
Median gross rent$1,152±$210$1,401$1,274no clear change
Renters paying 35% or more of income on rent53.5%±16.5 pts38.1%39.0%no clear change
Median monthly owner costs, with a mortgage$1,670±$90$2,137$1,987–
Owner-occupied homes62.1%±8.0 pts82.7%67.1%no clear change
Renter-occupied homes37.9%±8.0 pts17.3%32.9%–
Housing units2,968±286121,3295,457,452no clear change
Homeowner vacancy rate0.0%±2.1 pts0.5%1.0%–
Rental vacancy rate2.5%±4.1 pts2.9%5.0%–
Single-family detached homes62.5%±7.1 pts77.3%58.2%–
Mobile homes7.3%±4.9 pts0.7%2.3%–
Built 2020 or later0.0%±1.3 pts1.1%0.7%–
Built 2010 to 20193.1%±2.7 pts4.4%5.0%–
Built 1939 or earlier22.7%±7.1 pts8.0%20.2%–
Households with no vehicle5.8%±4.0 pts3.5%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 Marengo Township work and get to work?

79.5% of Marengo Township's workers drive alone and 8.8% work from home. The average trip to work takes 30.7 minutes. The unemployment rate in 2020-2024 averaged 8.8%.

Work and commuting, ACS 2020-2024 5-year estimates (workers 16 and over)
MeasureMarengo TownshipMcHenry CountyIllinoisChange since 2015-2019
In the labor force (age 16+)61.6%±5.3 pts69.7%65.0%–
Unemployment rate8.8%±5.4 pts4.7%5.8%+6.3 pts
Drove alone to work79.5%±5.8 pts72.9%65.9%–
Carpooled10.6%±5.8 pts7.7%7.8%–
Public transportation0.0%±1.2 pts1.3%5.8%–
Walked0.3%±0.5 pts1.1%2.8%–
Worked from home8.8%±3.1 pts16.1%15.9%+5.0 pts
Mean travel time to work30.7 min±3.230.1 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 Marengo Township?

1 census tract lies mostly in Marengo Township, and 1 more reaches into it (2020 census blocks).

Census tracts in Marengo Township, ACS 2020-2024 5-year estimates
TractResidents, 2020-2024Median household incomeMedian home valueShare of tract in Marengo Township
Tract 8710.03McHenry County3,754 $102,826 $240,50097%
Tract 8710.04McHenry County6,669 $97,694 $313,80028%

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 Marengo Township) · Census block assignment files

How does Marengo Township compare with other places in Illinois?

By the Census Bureau's July 2025 estimates, Marengo Township is the 1,660th-most populous of the 16,079 U.S. towns and townships that have one and the 186th-most populous of 1,407 in Illinois.

Marengo Township ranks 760th of 1,380 places in Illinois with 1,000 or more residents and a reliable estimate, by median household income.

Marengo 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 estimate186th1,407
Growth 2020-2025 (PEP)149th1,347
Residents per square mile899th1,383
Median household income760th1,380
Per capita income713th1,383
Median home value439th1,379
Median gross rent412th1,280
Poverty rate365th1,119
Bachelor's degree or higher935th1,369
Median age1,325th1,383
Owner-occupied share1,251st1,382
Work from home688th1,015
Travel time to work235th1,382

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

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

16 of the 57 figures for Marengo 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 Marengo 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.