| Place Name | Grassflat |
| Place Type | Census Designated Place |
| ZIP Code(s) | 16839 |
| County | Clearfield County |
| Area Code(s) | 814 |
| Timezone | Eastern Daylight Time (EDT) |
| Population (2022) | 481 |
| Population Growth Rate (2010-19) | -6.26% |
| Majority Ethnicity | White 100% |
| Metro/Micro Stats Area | DuBois, PA |
| US Congressional District(s) | Pennsylvania 5th |
| State House Districts | 73 |
| State Senate Districts | 35 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 100% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |