The 2020 census found 1,746 people in the township.

Located in the western part of the county, it borders the following townships: No municipalities are located in Spencer Township, although the unincorporated community of Frankfort lies in the township's west.

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

[4] 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,[5] 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.