| Place Name | Seneca |
| Place Type | Village |
| ZIP Code(s) | 61360 |
| County | LaSalle County Grundy County |
| Area Code(s) | 815,779 |
| Timezone | Central Daylight Time (CDT) |
| Population (2022) | 2,476 |
| Population Growth Rate (2010-19) | -0.76% |
| Majority Ethnicity | White 90.72% |
| Metro/Micro Stats Area | Ottawa, IL |
| US Congressional District(s) | Illinois 16th |
| State House Districts | 75 |
| State Senate Districts | 38 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 90.72% |
| African American | 1.38% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 7.9% |