[3] Reserve Township was named for a broader area of land, including the township, which the state had reserved from sale for its own purposes.

[5] According to the United States Census Bureau, the township has a total area of 2.0 square miles (5.2 km2), all land.

As of the census[12] of 2000, there were 3,856 people, 1,547 households, and 1,087 families residing in the township.

25.1% of all households were made up of individuals, and 11.8% had someone living alone who was 65 years of age or older.

Reserve Township is served by the Shaler Area School District.