Listed on the National Register of Historic Places in 1986, the former U.S. Post Office (1932) located at 50 Kearney Square was built by the federal government as Lowell's post office. The building is one of many in Lowell to have served as a post office through the years. A distinguished example of Neoclassical architecture, it was designed by one of Lowell’s only native architects at the time, George Augustine Daidy.
Two Massachusetts Cotton Mills boardinghouses (1839-41) were originally located here which were demolished in 1910 and replaced by a five-story storehouse. The site was purchased for the post office in 1929, the existing storehouse demolished, and construction began on the post office in August, 1930. It opened in January, 1932 after postal operations were transferred from the former location at 89 Appleton Street.