Portland township
- County:
- Whiteside County
- County Seat:
- No
- Area (mi²):
- 34.701
- State:
- Illinois
Portland township is located in Whiteside County, Illinois. Portland township has a 2026 population of 427. Portland township is currently growing at a rate of 0.23% annually but its population has decreased by -1.39% since the most recent census, which recorded a population of 433 in 2020.
The median household income in Portland township is $118,504 with a poverty rate of 0%. The median age in Portland township is 45.5 years: 45.5 years for males, and 49 years for females. For every 100 females there are 150.9 males.