The 2020 census found 3,011 people in the township.

Located in the southwestern part of the county, it borders the following townships: Several populated places are located in Smithfield Township: Smithfield Township was founded in 1805.

It takes its name from the village of Smithfield, which predates its establishment.

[5] 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,[6] 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.