City · Iowa
Thornton, Iowa
Thornton, city, in Cerro Gordo County, Iowa. Thornton had 391 residents on July 1, 2025 by the Census Bureau's estimate, down 3.5% since 2020; the 2020 Census counted 400 and the ACS 2020-2024 5-year estimates put it at 514 (±113). GEOID 1977880.
Residents, July 2025 estimate
391
Census Bureau estimate (no margin published)
2020 Census count: 400 · ACS 2020-2024: 514 ±113
Median household income
$67,031
±$9,327 (90% margin)
Iowa: $75,059
Median home value
$115,500
±$34,324 (90% margin)
Iowa: $208,000
Median gross rent
$839
±$160 (90% margin)
Iowa: $972
Where is Thornton and what county is it in?
Thornton is a city in Cerro Gordo County, Iowa. It covers 1.2 square miles of land, 322 residents per square mile in 2020.
Thornton is in the Mason City, IA micropolitan statistical area, which takes in 2 counties (Census Bureau delineation, July 2023).
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Thornton, and is it growing?
The Census Bureau estimates that 391 people lived in Thornton on July 1, 2025, down 3.5% since 2020, while Iowa grew 1.5%. The 2020 Census counted 400 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 514 (±113).
| Measure | Thornton | Cerro Gordo County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 514 ±113 | 42,632 | no clear change |
| Households | 231 ±53 | 19,538 | no clear change |
| Average household size | 2.23 ±0.27 | 2.13 | no clear change |
| Housing units | 244 ±54 | 22,786 | no clear change |
Thornton's population since 2000
From 422 in 2000 to 391 in 2025: down 7.3%. The 2000, 2010 and 2020 figures are census counts, each for Thornton 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.
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 Thornton?
The median resident of Thornton is 34.5 years old; 23.0% are under 18 and 20.2% are 65 or older. The largest group is non-Hispanic white residents at 88.9%, then Hispanic or Latino residents (of any race) at 9.1%.
| Measure | Thornton | Cerro Gordo County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 34.5 ±7.3 | 44.0 | no clear change |
| Under 18 years | 23.0% ±7.5 pts | 20.8% | – |
| 65 years and over | 20.2% ±11.7 pts | 23.5% | – |
| Male | 49.8% ±5.1 pts | 49.4% | – |
| Hispanic or Latino (any race) | 9.1% ±5.0 pts | 5.6% | – |
| White alone, not Hispanic | 88.9% ±4.7 pts | 88.2% | no clear change |
| Black or African American alone, not Hispanic | 0.0% ±4.7 pts | 1.9% | – |
| Asian alone, not Hispanic | 0.2% ±0.4 pts | 1.2% | – |
| American Indian and Alaska Native alone, not Hispanic | 0.0% ±4.7 pts | 0.2% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±4.7 pts | 0.6% | – |
| Two or more races, not Hispanic | 1.6% ±1.7 pts | 2.2% | – |
| Some other race alone, not Hispanic | 0.2% ±0.5 pts | 0.0% | – |
| Born outside the United States | 0.6% ±0.9 pts | 2.6% | – |
| Speak a language other than English at home (age 5+) | 2.1% ±1.8 pts | 3.7% | – |
| Civilian veterans (age 18+) | 4.8% ±2.5 pts | 7.9% | – |
| With a disability | 11.7% ±5.2 pts | 14.5% | – |
| No health insurance coverage | 2.9% ±2.2 pts | 4.5% | – |
| High school graduate or higher (age 25+) | 92.7% ±4.8 pts | 94.8% | – |
| Bachelor's degree or higher (age 25+) | 17.2% ±5.7 pts | 24.0% | no clear change |
| Graduate or professional degree (age 25+) | 2.6% ±2.3 pts | 7.9% | – |
| Lived in the same house a year earlier | 93.5% ±4.0 pts | 88.6% | – |
| Moved from another state in the past year | 0.0% ±4.8 pts | 2.3% | – |
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 Thornton earn?
Half of Thornton's 231 households earn less than $67,031 a year (±$9,327), against $68,189 in Cerro Gordo County and $75,059 in Iowa. In 2015-2019 it was $59,740 in 2024 dollars; the margins of error cannot tell the two periods apart. 9.3% of residents live below the poverty line.
| Measure | Thornton | Cerro Gordo County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $67,031 ±$9,327 | $68,189 | no clear change |
| Mean household income | $75,942 ±$6,951 | $92,087 | – |
| Per capita income | $31,958 ±$4,148 | $41,560 | no clear change |
| People below the poverty line | 9.3% ±5.2 pts | 10.6% | no clear change |
| Children under 18 below the poverty line | 13.6% ±12.4 pts | 13.7% | – |
| Households receiving SNAP | 5.6% ±4.3 pts | 9.0% | – |
| Households with a computer | 99.6% ±0.9 pts | 94.7% | – |
| Households with a broadband subscription | 95.7% ±2.8 pts | 89.2% | – |
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 Thornton?
Owners occupy 84.0% of Thornton's occupied homes and renters 16.0%. The median owner-occupied home is valued at $115,500 by its owner (±$34,324). The median renter pays $839 a month including utilities.
| Measure | Thornton | Cerro Gordo County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $115,500 ±$34,324 | $166,400 | no clear change |
| Median gross rent | $839 ±$160 | $850 | no clear change |
| Renters paying 35% or more of income on rent | 29.0% ±22.0 pts | 28.5% | – |
| Median monthly owner costs, with a mortgage | $1,094 ±$213 | $1,365 | – |
| Owner-occupied homes | 84.0% ±8.8 pts | 70.4% | no clear change |
| Renter-occupied homes | 16.0% ±8.8 pts | 29.6% | – |
| Housing units | 244 ±54 | 22,786 | no clear change |
| Homeowner vacancy rate | 2.0% ±3.1 pts | 0.4% | – |
| Rental vacancy rate | 7.5% ±11.2 pts | 3.3% | – |
| Single-family detached homes | 92.6% ±6.3 pts | 76.5% | – |
| Mobile homes | 2.0% ±2.3 pts | 3.2% | – |
| Built 2020 or later | 0.4% ±1.0 pts | 1.1% | – |
| Built 2010 to 2019 | 0.8% ±1.2 pts | 3.7% | – |
| Built 1939 or earlier | 40.6% ±12.0 pts | 27.6% | – |
| Households with no vehicle | 1.3% ±1.4 pts | 5.0% | – |
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 many new homes is Thornton building?
Builders took permits for 0 new housing units in Thornton in 2025 (0 in single-family houses), 0.0 per 1,000 residents against 4.2 across Iowa.
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 Thornton work and get to work?
70.6% of Thornton's workers drive alone. The average trip to work takes 25.2 minutes.
| Measure | Thornton | Cerro Gordo County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 64.8% ±14.1 pts | 63.2% | – |
| Unemployment rate | 1.5% ±1.5 pts | 2.6% | – |
| Drove alone to work | 70.6% ±8.8 pts | 80.1% | – |
| Carpooled | 16.1% ±8.5 pts | 7.6% | – |
| Public transportation | 0.0% ±9.3 pts | 0.8% | – |
| Walked | 3.1% ±2.0 pts | 3.3% | – |
| Worked from home | 8.6% ±6.0 pts | 7.2% | – |
| Mean travel time to work | 25.2 min ±3.3 | 15.6 min | no 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 Thornton?
No census tract lies mostly in Thornton; 1 tract reaches into it (2020 census blocks).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 9510Cerro Gordo County | 2,617 | $63,563 |
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 Thornton) · Census block assignment files
How does Thornton compare with other places in Iowa?
By the Census Bureau's July 2025 estimates, Thornton is the 14,215th-most populous of the 19,476 U.S. incorporated places that have one and the 489th-most populous of 939 in Iowa.
Thornton 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.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 489th | 939 |
Thornton's figures with every place in Iowa (CSV)
Every place in Iowa, sortable · Compare Thornton 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 Thornton?
23 of the 57 figures for Thornton 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 Thornton 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' public schools in Thornton.