| Place Name | Westby |
| Place Type | Town |
| ZIP Code(s) | 59275 |
| County | Sheridan County |
| Area Code(s) | 406 |
| Timezone | Mountain Standard Time (MST) |
| Population (2022) | 174 |
| Population Growth Rate (2010-19) | -0.60% |
| Majority Ethnicity | White 100% |
| US Congressional District(s) | Montana At-Large |
| State House Districts | 34 |
| State Senate Districts | 17 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 100% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |