Township · Illinois

South Ottawa Township, Illinois

South Ottawa Township, township, in LaSalle County, Illinois. South Ottawa Township had 8,299 residents on July 1, 2025 by the Census Bureau's estimate, down 0.6% since 2020; the 2020 Census counted 8,343 and the ACS 2020-2024 5-year estimates put it at 8,322 (±21). GEOID 1709971110.

Residents, July 2025 estimate

8,299

Census Bureau estimate (no margin published)
2020 Census count: 8,343 · ACS 2020-2024: 8,322 ±21

Median household income

$84,054

±$5,359 (90% margin)
Illinois: $83,390

Median home value

$169,500

±$12,087 (90% margin)
Illinois: $263,300

Median gross rent

$935

±$58 (90% margin)
Illinois: $1,274

Where is South Ottawa Township and what county is it in?

South Ottawa Township is a township in LaSalle County, Illinois. It covers 19.7 square miles of land, 424 residents per square mile in 2020.

Part of Ottawa (city) also lies in it.

South Ottawa Township is in the Ottawa, IL micropolitan statistical area, which takes in 3 counties (Census Bureau delineation, July 2023).

South Ottawa Township (marked with a dot) in LaSalle 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 South Ottawa Township, and is it growing?

The Census Bureau estimates that 8,299 people lived in South Ottawa Township on July 1, 2025, down 0.6% since 2020, in line with Illinois (−0.8%). The 2020 Census counted 8,343 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 8,322 (±21).

  • July 2020→2021 −11 (8,336)
  • 2021→2022 −62 (8,274)
  • 2022→2023 +29 (8,303)
  • 2023→2024 +7 (8,310)
  • 2024→2025 −11 (8,299)
ACS 2020-2024 5-year estimates (counts) with the change from 2015-2019
MeasureSouth Ottawa TownshipLaSalle CountyIllinoisChange since 2015-2019
Total population8,322±21108,71412,694,798+251
Households3,287±23745,3735,036,449no clear change
Average household size2.44±0.172.332.46no clear change
Housing units3,493±23849,8435,457,452no clear change

South Ottawa Township's population since 2000

From 8,222 in 2000 to 8,299 in 2025: up 0.9%. The 2000, 2010 and 2020 figures are census counts, each for South Ottawa 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 8,222
  • 2005 (estimate) 8,220
  • 2010 Census 8,290
  • 2015 (estimate) 8,133
  • 2020 Census 8,343
  • 2025 (estimate) 8,299

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 South Ottawa Township?

The median resident of South Ottawa Township is 40.8 years old; 24.8% are under 18 and 21.0% are 65 or older. The largest group is non-Hispanic white residents at 87.0%, then Hispanic or Latino residents (of any race) at 9.0%. 2.7% 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.
MeasureSouth Ottawa TownshipLaSalle CountyIllinoisChange since 2015-2019
Median age40.8±4.042.239.0no clear change
Under 18 years24.8%±3.8 pts21.2%21.8%–
65 years and over21.0%±2.5 pts19.9%17.0%–
Male45.2%±4.0 pts51.0%49.4%–
Hispanic or Latino (any race)9.0%±3.3 pts11.2%18.8%no clear change
White alone, not Hispanic87.0%±3.6 pts82.1%58.1%no clear change
Black or African American alone, not Hispanic0.3%±0.3 pts2.5%13.3%–
Asian alone, not Hispanic0.5%±0.6 pts0.8%5.9%–
American Indian and Alaska Native alone, not Hispanic0.0%±0.4 pts0.0%0.1%–
Native Hawaiian and Other Pacific Islander alone, not Hispanic0.0%±0.1 pts0.0%0.0%–
Two or more races, not Hispanic3.1%±2.0 pts3.1%3.4%–
Some other race alone, not Hispanic0.0%±0.4 pts0.3%0.4%–
Born outside the United States2.7%±1.3 pts3.9%14.7%no clear change
Speak a language other than English at home (age 5+)2.5%±1.6 pts7.9%24.0%–
Civilian veterans (age 18+)7.9%±2.5 pts7.7%4.8%–
With a disability13.3%±2.7 pts13.9%12.1%–
No health insurance coverage3.6%±1.9 pts4.0%6.9%no clear change
High school graduate or higher (age 25+)91.7%±3.9 pts91.8%90.5%–
Bachelor's degree or higher (age 25+)27.1%±5.5 pts20.5%37.8%no clear change
Graduate or professional degree (age 25+)8.2%±2.8 pts6.5%15.3%–
Lived in the same house a year earlier89.5%±4.2 pts90.9%88.9%–
Moved from another state in the past year1.1%±0.9 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 South Ottawa Township earn?

Half of South Ottawa Township's 3,287 households earn less than $84,054 a year (±$5,359), against $73,045 in LaSalle County and $83,390 in Illinois. In 2015-2019 the median was $72,125 in 2024 dollars, so it rose by $11,929 after inflation. 13.5% 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
MeasureSouth Ottawa TownshipLaSalle CountyIllinoisChange since 2015-2019
Median household income$84,054±$5,359$73,045$83,390+$11,929
Mean household income$103,846±$12,832$93,009$115,638–
Per capita income$42,276±$5,332$39,375$46,406no clear change
People below the poverty line13.5%±5.0 pts13.9%11.8%no clear change
Children under 18 below the poverty line19.1%±12.0 pts21.0%15.1%no clear change
Households receiving SNAP19.9%±5.1 pts14.8%13.8%–
Households with a computer91.0%±4.1 pts93.4%95.2%–
Households with a broadband subscription84.3%±5.7 pts87.4%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 South Ottawa Township?

Owners occupy 75.8% of South Ottawa Township's occupied homes and renters 24.2%. The median owner-occupied home is valued at $169,500 by its owner (±$12,087). The median renter pays $935 a month including utilities, and 42.3% of renters pay 35% or more of their income on rent.

Housing, ACS 2020-2024 5-year estimates. Home values are owners' own estimates.
MeasureSouth Ottawa TownshipLaSalle CountyIllinoisChange since 2015-2019
Median home value (owner-occupied)$169,500±$12,087$161,900$263,300no clear change
Median gross rent$935±$58$928$1,274−$153
Renters paying 35% or more of income on rent42.3%±14.6 pts36.4%39.0%no clear change
Median monthly owner costs, with a mortgage$1,597±$72$1,476$1,987–
Owner-occupied homes75.8%±5.2 pts74.4%67.1%+8.0 pts
Renter-occupied homes24.2%±5.2 pts25.6%32.9%–
Housing units3,493±23849,8435,457,452no clear change
Homeowner vacancy rate0.0%±1.5 pts1.2%1.0%–
Rental vacancy rate0.0%±4.6 pts3.9%5.0%–
Single-family detached homes76.9%±5.4 pts78.8%58.2%–
Mobile homes0.5%±0.7 pts4.2%2.3%–
Built 2020 or later0.0%±1.1 pts0.7%0.7%–
Built 2010 to 20192.5%±2.9 pts2.9%5.0%–
Built 1939 or earlier19.9%±4.7 pts24.6%20.2%–
Households with no vehicle4.8%±3.3 pts6.0%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 South Ottawa Township work and get to work?

86.1% of South Ottawa Township's workers drive alone and 4.9% work from home. The average trip to work takes 25.9 minutes. The unemployment rate in 2020-2024 averaged 4.7%.

Work and commuting, ACS 2020-2024 5-year estimates (workers 16 and over)
MeasureSouth Ottawa TownshipLaSalle CountyIllinoisChange since 2015-2019
In the labor force (age 16+)63.2%±3.8 pts61.3%65.0%–
Unemployment rate4.7%±2.9 pts5.4%5.8%no clear change
Drove alone to work86.1%±4.0 pts83.0%65.9%–
Carpooled6.0%±2.6 pts8.2%7.8%–
Public transportation0.5%±0.7 pts0.2%5.8%–
Walked0.5%±0.7 pts1.8%2.8%–
Worked from home4.9%±1.9 pts5.1%15.9%no clear change
Mean travel time to work25.9 min±4.126.0 min27.8 min+5.6 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 South Ottawa Township?

2 census tracts lie mostly in South Ottawa Township, and 3 more reach into it (2020 census blocks). Their median household incomes run from $81,181 (Tract 9636) to $84,113 (Tract 9635).

Census tracts in South Ottawa Township, ACS 2020-2024 5-year estimates
TractResidents, 2020-2024Median household incomeMedian home valueShare of tract in South Ottawa Township
Tract 9635LaSalle County4,848 $84,113 $163,90093%
Tract 9636LaSalle County3,346 $81,181 $168,900100%
Tract 9622LaSalle County4,782 $108,614 $242,8003%
Tract 9640LaSalle County2,478 $92,667 $225,1006%
Tract 9623LaSalle County6,970 $96,159 $246,4001%

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 South Ottawa Township) · Census block assignment files

How does South Ottawa Township compare with other places in Illinois?

By the Census Bureau's July 2025 estimates, South Ottawa Township is the 1,495th-most populous of the 16,079 U.S. towns and townships that have one and the 173rd-most populous of 1,407 in Illinois.

South Ottawa Township ranks 572nd of 1,380 places in Illinois with 1,000 or more residents and a reliable estimate, by median household income.

South Ottawa 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 estimate173rd1,407
Growth 2020-2025 (PEP)376th1,347
Residents per square mile797th1,383
Median household income572nd1,380
Per capita income505th1,383
Median home value688th1,379
Median gross rent675th1,280
Poverty rate352nd1,119
Bachelor's degree or higher561st1,369
Median age711th1,383
Owner-occupied share785th1,382
Work from home959th1,015
Travel time to work663rd1,382

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

Every place in Illinois, sortable · Compare South Ottawa 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 South Ottawa Township?

14 of the 57 figures for South Ottawa 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 South Ottawa 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.