The 2020 census reported 1,461 people living in the township.

Located in the northwestern part of the county, it borders the following townships: Two villages are located in Jefferson Township: Nellie in the west, and Warsaw in the east.

[4][5] It is one of twenty-four Jefferson Townships statewide.

[6] 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,[7] 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.