Chambersburg Township is located in Pike County, Illinois. As of the 2018 census, its population was 241 and it contained 89 housing units.
Chambersburg Township was named for a family of first settlers.
According to the census conducted in 2018, the township has a total area of , of which (or 98.18%) is land and (or 1.82%) is water.
The township had 138 males and 103 females.