The 2020 census found 3,067 people in the township.

[3] Located in the southwestern corner of the county, it borders the following townships: The village of Spencerville is located in southern Spencer Township.

Statewide, other Spencer Townships are located in Guernsey, Lucas, and Medina counties and formerly in Hamilton County.

The township is governed by a three-member board of trustees, who are elected in November of odd-numbered years to a four-year term beginning on the following January 1.

There is also an elected township fiscal officer,[4] who serves a four-year term beginning on April 1 of the year after the election, which is held in November of the year before the presidential election.