Illinois township
- County:
- Sumner County
- County Seat:
- No
- Area (mi²):
- 36.401
- State:
- Kansas
Illinois township is located in Sumner County, Kansas. Illinois township has a 2026 population of 171. Illinois township is currently declining at a rate of 0% annually and its population has increased by 0.59% since the most recent census, which recorded a population of 170 in 2020.
The median household income in Illinois township is $135,313 with a poverty rate of 0%. The median age in Illinois township is 54.1 years: 54.3 years for males, and 51 years for females. For every 100 females there are 100.0 males.