The addition on the west and south side of the building that was added in the 1930´s included indoor plumbing with marble restrooms, shower room and marble stairs leading to the second floor. When the Post Office outgrew this site in the 1960´s, a new post office facility was built at 321 West Main Street, and the former Post Office facility was purchased by the City of Ottawa during the administration of Mayor Philip Bailey in 1962 for $35,000.
301 West Madison Street officially became City Hall on September 13, 1965 when Mayor Dan Riordan moved the City´s business offices from 422 LaSalle Street where they shared offices with the Police and Fire Departments. This relocation brought the daily business of the City back to the same block where two other City Halls once stood; one on the north side of Madison Street between Clinton Street and Fulton Street that was destroyed by The Great Fire in 1881 and another at 315 West Madison Street (1926-1937).
The 2002 renovation has successfully accomplished a blend of the old with the new to create modern-day offices while retaining the building´s unique amenities and historic flavor.