The authors agree that this surname derives from the numerous Italian place names containing the word isola ("island"). E. De Felice specifies that the most likely places of origin are found in Liguria: Isola (in the Genoa and La Spezia areas), Isola del Cantone (Genoa area), Isola Sant'Antonio (Alessandria area) and Isolabona (Imperia area).

E. Rossoni broadens this perspective and notes that the surname is present in various parts of Italy, given the abundance of place names of that form. He proposes a possible original cluster in the Genoa area, from which branches would have spread towards the Cagliari area and towards other coastal localities of southern Italy.

G. P. Holmes adds that isola also functioned as a feminine given name with the meaning "island", which opens the possibility that in some cases the surname derives from a personal name and not directly from a place name.