Blair township
- County:
- Clay County
- County Seat:
- No
- Area (mi²):
- 36.195
- State:
- Illinois
Blair township is located in Clay County, Illinois. Blair township has a 2026 population of 596. Blair township is currently declining at a rate of -1% annually and its population has decreased by -4.03% since the most recent census, which recorded a population of 621 in 2020.
The median household income in Blair township is $61,964 with a poverty rate of 18.44%. The median age in Blair township is 60.3 years: 63.3 years for males, and 56.6 years for females. For every 100 females there are 82.1 males.