According to the United States Census Bureau, the township has a total area of 20.2 square miles (52.2 km2), all land.

This township includes the unincorporated communities of Smithville, New Providence, Union, and Truce.

At the time of the 2000 census, there were 6,651 people, 2,387 households, and 1,847 families living in the township.

There were 2,486 housing units at an average density of 123.4 per square mile (47.6/km2).

For every one hundred females who were aged eighteen or older, there were 96.8 males.