Waltham Township is located in LaSalle County, Illinois. As of the 2010 census, its population was 446 and it contained 200 housing units.
According to the 2010 census, the township has a total area of 37.01 square miles (95.9 km2), all land.
- ^ a b "Population, Housing Units, Area, and Density: 2010 - County -- County Subdivision and Place -- 2010 Census Summary File 1". United States Census. Retrieved 2013-05-28.
Coordinates: 41°24′43″N 88°59′23″W / 41.41194°N 88.98972°W