Since 1856, Molson Bank had a building on St. James Street, which quickly became too small.
An architectural competition was held and architects George and John James Browne won.
It had to enlarge the building in 1900 and 1911, which, at the end of the work, covered the entire surface of the lot.
Unusually, the first floor was extended to Notre-Dame Street, within the Insurance Exchange building built behind the Molson Bank in 1923-1924.
In 2009, the Molson Bank building was occupied by government and legal offices.