This property is one of Georgetown’s few remaining nineteenth–century large estates and is intact to its nineteenth century appearance. The Williams-Addison House was individually designated as a historic landmark, and placed on the DC Inventory of Historic Sites in 1964. It is included in the Large Houses and Mansions subsection of Georgetown (1751-1895) section of the Inventory. Further, it is also a contributing building in the Georgetown Historic District.

The Landmark Amendment states, in part:

This three-quarter acre lot remains a significant open space in Georgetown and recalls the character of Georgetown Heights during Georgetown’s nineteenth century heyday. The property’s continuing existence as a single-family residence on a large lot illustrates a long and significant association with two of Georgetown’s oldest families, the Bealls and the Williamses, and establishes their relationship with the internationally-influential Russian Bodisco family. Its association with these families reveals significant information about the patterns of original subdivision, architecture, land holding, and inheritance of nineteenth century Georgetown . . . . Finally, the property carries additional significance as the subsequent home to, among others, notable philanthropist Clarence Phelps Dodge and prominent journalist Alfred Friendly later in the twentieth century.