| Place Name | Onalaska |
| Place Type | Census Designated Place |
| ZIP Code(s) | 98570 |
| County | Lewis County |
| Area Code(s) | 360 |
| Timezone | Pacific Standard Time (PST) |
| Population (2022) | 731 |
| Population Growth Rate (2010-19) | 5.80% |
| Majority Ethnicity | White 100% |
| Metro/Micro Stats Area | Centralia, WA |
| US Congressional District(s) | Washington 3rd |
| State House Districts | 20 |
| State Senate Districts | 20 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 100% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |