| Place Name | Waterloo |
| Place Type | City |
| ZIP Code(s) | 62298 |
| County | Monroe County |
| Area Code(s) | 618 |
| Timezone | Central Daylight Time (CDT) |
| Population (2022) | 9,826 |
| Population Growth Rate (2010-19) | 12.25% |
| Majority Ethnicity | White 96% |
| Metro/Micro Stats Area | St. Louis, MO-IL |
| US Congressional District(s) | Illinois 12th |
| State House Districts | 116 |
| State Senate Districts | 58 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 96% |
| African American | 0.47% |
| Hispanic | 0.47% |
| Asian | 1.56% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 1.51% |