The surname Binasco is of clearly toponymic origin and is linked to localities of northern Italy. According to E. De Felice, it is a Lombard surname formed from the place name Binasco (Milan area), following the usual model of identification by place of provenance.

Along the same lines, E. Rossoni confirms this derivation, specifying that the surname is typical of the Alessandria area, especially in Novi Ligure, and that it refers to the place name Binasco in the province of Pavia. This double geographical reference reflects the movements of families from their place of origin towards other nearby areas.

Taken together, both interpretations agree in pointing to a strictly toponymic origin, where the surname identifies people coming from a specific locality, in this case Binasco, with subsequent diffusion in neighbouring regions of northern Italy.