Plum Hill township
- County:
- Washington County
- County Seat:
- No
- Area (mi²):
- 37.816
- State:
- Illinois
Plum Hill township is located in Washington County, Illinois. Plum Hill township has a 2026 population of 489. Plum Hill township is currently declining at a rate of -0.2% annually and its population has decreased by -0.81% since the most recent census, which recorded a population of 493 in 2020.
The median household income in Plum Hill township is $101,167 with a poverty rate of 2.84%. The median age in Plum Hill township is 53 years: 53.5 years for males, and 49.9 years for females. For every 100 females there are 95.0 males.