The authors agree that the surname derives from the medieval name Italiano —the equivalent of the modern Italo—, which in the multi-ethnic context of medieval Italy underlined a relation to the family's ethnic origins. Both also point to a second hypothesis: that Italiano is an aphaeresis of the medieval name Vitaliano, though in that case it would be a secondary source. In either case, the surname arises from the fixing as a surname of the personal names of the first bearers, or else from nicknames referring to their provenance.

E. Rossoni indicates that the variant Italiani is fairly rare and is concentrated in isolated areas: the area between the Marche and the Perugia area, a strip between the Teramo and Pescara areas, and another between the Rome and Latina areas. The variant Italiano, by contrast, is typical of southern Italy, with an important presence in the Reggio Calabria and Messina areas, in the Palermo area, and in the Bari and Brindisi areas.

F. Miranda adds that the surname is found across every Italian region, with specific areas in Sicily, Calabria, Lombardy, Piedmont, Lazio, Campania, Apulia, Tuscany, Liguria and Emilia-Romagna. In Sicily it is present in every province, with concentrations especially in the Messina, Palermo, Caltanissetta, Catania and Agrigento areas and in the Enna area.