Marengo city, Illinois
Official LSAD Designation: Marengo city • Census GEOID: 1746786
• McHenry County
Demographics & Population Profile
Population and demographics for Marengo city.
| Demographic Variable | Estimate / Count | Margin of Error | Period | Source |
|---|---|---|---|---|
| Total Population (2025 PEP Estimate) | 7,737 | — | 2025 | Census |
| Median Age | 31.9 yrs | ±4.8 | 2020-2024 | Census ACS 5-Year 2024 |
| Total Households | 2,719 | ±230 | 2020-2024 | Census ACS 5-Year 2024 |
Source: U.S. Census Bureau (PEP, ACS 5-Year).