| Place Name | Spencer |
| Place Type | City |
| ZIP Code(s) | 51301 |
| County | Clay County |
| Area Code(s) | 712 |
| Timezone | Central Standard Time (CST) |
| Population (2022) | 11,204 |
| Population Growth Rate (2010-19) | 0.82% |
| Majority Ethnicity | White 94.22% |
| Metro/Micro Stats Area | Spencer, IA |
| US Congressional District(s) | Iowa 4th |
| State House Districts | 2 |
| State Senate Districts | 1 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 94.22% |
| African American | 0.12% |
| Hispanic | 0.21% |
| Asian | 0.72% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 4.74% |