| Place Name | Penn Township (Jefferson County) |
| Place Type | Township |
| ZIP Code(s) | 52540 52556 52585 |
| County | Jefferson County |
| Area Code(s) | 319,641 |
| Timezone | Central Daylight Time (CDT) |
| Population (2021) | 333 |
| Majority Ethnicity | White 100% |
| Metro/Micro Stats Area | Fairfield, IA |
| US Congressional District(s) | Iowa 2nd |
| State House Districts | 82 |
| State Senate Districts | 41 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 100% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |