The surname is present throughout Italy, with specific, localized areas of concentration in the provinces of Imperia, Sassari, Bologna, and Perugia, as well as in scattered communities across southern Italy. E. Rossoni notes that the variant Melas is typically Sardinian, concentrated in the province of Cagliari — in localities such as Guasila, Cagliari, and Selegas — as well as at Bosa in the province of Oristano, and at Sanluri and Villamassargia.

On the question of origin, Rossoni proposes that both forms derive from the Latin personal name Mela, attested in the first-century geographer and writer Pomponius Mela, author of De situ orbis, considered the first work to treat geography systematically. He does not rule out, however, that in some cases the surname arose from nicknames connected to the word for the fruit of the same form — that is, the apple. This second possibility is supported by the source Surnames in Italy, which considers the apple tree (Italian mela) the point of origin for the surname.

P. Regati identifies the surname as characteristic of the area of Imperia, a detail consistent with Rossoni's geographic observations for that province.