[1] According to the 2021 census gazetteer files, Watson Township (T7N R6E) has a total area of 35.83 square miles (92.80 km2), all land.

As of the 2020 census[1] there were 3,188 people, 1,298 households, and 861 families residing in the township.

There were 1,329 housing units at an average density of 37.09 per square mile (14.32/km2).

The racial makeup of the township was 94.51% White, 0.06% African American, 0.00% Native American, 0.19% Asian, 0.00% Pacific Islander, 1.10% from other races, and 4.14% from two or more races.

28.10% of all households were made up of individuals, and 7.90% had someone living alone who was 65 years of age or older.