The first post office in the Iowa County town in Millersburg opened in 1852 with Hugh B. Lynch appointed as the first postmaster. In the 1880s, the post office began sharing space with an ice cream parlor and drug store. Those businesses ultimately were phased out, but postal operations continued in the building for over a century. A new post office was constructed in June 1993, with a dedication held two months later. The modern facility was handicapped-accessible and featured new key-based boxes.

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.

The Amana Colonies village of South Amana is well-known for its abundance of brick buildings and summer flower gardens. The post office, which has been in operation since 1874, occupies one of the many historic buildings in the community.

The unincorporated village of Homestead was not part of the original Amana Colonies settlement. It was added in 1861, six years after the original six communities were formed, to give the Colonies access to the railroad. Visitors to Homestead will find several original brick Amana dwellings. Though they are now privately owned by individual families, at time of construction, these homes served as the residence for three or four families at a time.

The Post Office in Homestead was in place before the community was incorporated into the Amana Colonies. The post office was originally established in 1852, more than 30 years before service was present in any other Amana village. It appears have remained in the same location since at least 1919, though its modern day appearance varies from the postcard: a ramp has been added added, chimneys removed, and supports now prop up the west wall of the building.