The Old Ashland Post Office was built in 1892-1893 from a design by Willoughby J. Edbrooke, the supervising architect for the U.S. Treasury Department. H. P. Padley, an architect from the Ashland branch of the Madison architectural firm of Conover and Porter, supervised its construction.

Like many other buildings in Ashland, the two-and-a-half story post office building was designed in the Richardsonian Romanesque style and was built of locally-quarried brownstone. The building displays the heavy massing and the rounded arches characteristic of the style. The roof is steeply pitched with numerous gables and dormers.

In the southeast corner of the building is a four-story square tower with a steep pyramidal roof. Because of its height and proximity to the bay, this tower originally served as a lookout and signal station for the harbor. The tower, which is open on the top level, was also used for taking meteorological observations.

A new post office building constructed in the late 1930s replaced this building. The Old Ashland Post Office building now houses the Ashland City Hall and is open during normal business hours.