How many people live in Grundy County, IL?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 53,800 people living in Grundy County, IL. That makes Grundy County the 25th-most populous county in Illinois. It is home to 0.42% of people living in the state.
53.8K
population of Grundy County, IL (2024)
0.42%
County share of the Illinois population (2024)
About 53,800 people lived in Grundy County, IL in 2024.
Population estimates, 2000–2024
What are Grundy County, IL’s age demographics?
About 8,600 Grundy County residents are aged 65 and older in 2024. That represents 16.1% of its population. For comparison, the age group represents 17.9% of Illinois’s population and 18% in the US overall.
Another 12,700 Grundy County residents, or 23.6% of the population, were children under 18. For comparison, the age group represents 21.2% of Illinois’s population and 21.6% in the US overall.
A higher share of Grundy County, IL's population is aged under 18 than the US as a whole.
Population estimates by age group, (2024)
What are Grundy County, IL’s racial and ethnic demographics?
Non-Hispanic white residents make up 82.1% of the Grundy County, IL population, higher than the national share of 57.5%.
In contrast, Grundy County’s non-Hispanic Black or African American population accounts for 2.4%, below the 12.6% nationwide, and the Hispanic population makes up 13% of the county, compared with 20% nationally.
Racial and ethnic make up differ based on location. These figures reflect how people identified their race alone (not in combination with other races), and separate out Hispanic or Latino ethnicity, following Census reporting standards.
Grundy County, IL has a higher share of a non-Hispanic white population than Illinois as a whole.
Population estimates by race and ethnicity, (2024)
The largest city or town in Grundy County, IL is Minooka with about 9,800 residents in 2024.
Cities and towns in Grundy County, IL ranked by population
Population (2024), includes only portions within county
| City or town | Population | |
|---|---|---|
| 1. | Minooka (pt.) | 9,755 |
| 2. | Morris (pt.) | 7,287 |
| 3. | Morris (pt.) | 5,347 |
| 4. | Channahon (pt.) | 4,520 |
| 5. | Coal City (pt.) | 3,776 |
| 6. | Wauponsee | 2,350 |
| 7. | Coal City (pt.) | 2,021 |
| 8. | Morris (pt.) | 1,953 |
| 9. | Diamond (pt.) | 1,417 |
| 10. | Gardner (pt.) | 1,360 |
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Methodology
USAFacts standardizes data, in areas such as time and demographics, to make it easier to understand and compare.
The analysis was generated with the help of AI and reviewed by USAFacts for accuracy.
Page sources
USAFacts endeavors to share the most up-to-date information available. We sourced the data on this page directly from government agencies; however, the intervals at which agencies publish updated data vary.
