[3] The city of Williamston occupies the southeast corner of the township, but the two are administered autonomously.

[5] As of the census[1] of 2000, there were 4,834 people, 1,692 households, and 1,416 families residing in the township.

There were 1,732 housing units at an average density of 58.9 per square mile (22.7/km2).

12.9% of all households were made up of individuals, and 4.0% had someone living alone who was 65 years of age or older.

The Williamston Community Schools serve most of Williamstown Township.