E. Rossoni distinguishes two related surnames: Monferrati, practically unique, which he places in the Ferrara area, and Monferrato, very rare, which he considers of Piedmontese origin. According to Rossoni, both would derive from the historical place name Monferrato, a district of hills situated south of the Po, between the Ligurian Apennines and the Asti and Alessandria areas, in Piedmont, which would indicate the place of origin of the founding ancestors.

F. De Laurentiis agrees that the base of the surname is the place name Monferrato and that it indicates provenance from that area.