| Place Name | Nassau Township |
| Place Type | Township |
| ZIP Code(s) | 51003 51041 |
| County | Sioux County |
| Area Code(s) | 712 |
| Timezone | Central Daylight Time (CDT) |
| Population (2021) | 2,266 |
| Majority Ethnicity | White 93.62% |
| US Congressional District(s) | Iowa 4th |
| State House Districts | 4 |
| State Senate Districts | 2 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 93.62% |
| African American | 0.43% |
| Hispanic | 0% |
| Asian | 0.86% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 5.09% |