The authors agree that the surname derives, by aphaeresis (suppression of the initial syllable or syllables), from personal names of Germanic origin ending in -berto, such as Alberto, Adalberto, Lamberto, Roberto, Umberto and Uberto. The shared root is the Germanic adjective berhta, meaning "splendid, illustrious, famous". From this base were formed hypocoristics such as Bertus, Berto and Berta, which over time became a surname.

F. Miranda also notes that Berto can be a direct continuation of Germanic names already autonomous since the 7th century, attested in Italy in the following century in the Latinised forms Bertus and Berto. These names were of probably Gothic and later Lombard and Frankish tradition. Miranda indicates that the surname is spread across around six hundred comuni, concentrated mainly in the Veneto, but with relevant presence in Lombardy, Piedmont, Lazio, Trentino-Alto Adige, Friuli-Venezia Giulia, Emilia-Romagna, the Marche, Tuscany, Campania, Sicily and Liguria. In Sicily it appears in the Catania, Enna, Messina, Ragusa and Syracuse areas.