| Place Name | Union Star |
| Place Type | Town |
| ZIP Code(s) | 64494 |
| County | DeKalb County |
| Area Code(s) | 816,975 |
| Timezone | Central Standard Time (CST) |
| Population (2022) | 421 |
| Population Growth Rate (2010-19) | -13.04% |
| Majority Ethnicity | White 87.59% |
| Metro/Micro Stats Area | St. Joseph, MO-KS |
| US Congressional District(s) | Missouri 6th |
| State House Districts | 2 |
| State Senate Districts | 12 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 87.59% |
| African American | 0% |
| Hispanic | 0.19% |
| Asian | 4.81% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 7.41% |