According to the Victorian Heritage Database,
The Trades Hall, like the grander Melbourne Port Authority Building, is designed in the contemporary Greek Revival style, providing for a dignified but conservative street facade. Restrained use of corniced trabeation and, within, the detailing and disposition of openings has been carefully executed to achieve simple elegance, although once past the facade the external envelope returns to a prosaic form . The building is a lower scale versio of contemporary designs such as the Malop street National Bank and, to a lesser extent, the CMI building.