In November 1965, a contract was awarded to resident Harold D. Burkholder to build a new post office in the Iowa County community of Parnell. With an interior space of nearly 1,200 square feet, the new post office had air conditioning along with a separate parking area. The new Parnell Post Office building was officially dedicated in September 1966.

The Williamsburg Journal-Tribune reported the dedication brought 700 people from Parnell and the surrounding area. The dedication included a flag-raising ceremony from the local American Legion group, a benediction from a local Mennonite pastor, and a ribbon-cutting ceremony performed by Parnell’s mayor. The dedication was followed by an open house.

Postal service originated in Parnell in November 1884 under the Callan moniker, in recognition of the large property ownership by the Callan family at the time. The name was changed following the official establishment of Parnell when the Milwaukee Railroad line was connected to the community. The Post Office had a variety of locations, including local grocery and hardware stores.