The surname Alba has a double origin, which can be either anthroponymic or toponymic. According to E. De Felice, it is widespread mainly in central-southern Italy, especially in Puglia and Sicily, and can derive from the feminine personal name Alba, in which case it would be a matronymic (that is, a surname formed from a woman's name). Alternatively, it can originate in one of the numerous place names Alba present in various Italian regions.

E. De Felice also notes that, in southern Italy, the presence of the Spanish surname Alba may have influenced its spread, which introduces a possible overlap of onomastic traditions in historical contexts of cultural contact.

For his part, E. Rossoni agrees on these two interpretive lines, indicating that the surname can derive both from the feminine name Alba and from place names with that root, thus reinforcing the idea of a non-univocal origin.

Taken together, both interpretations agree in noting that Alba may have arisen both as a matronymic and by geographical reference, with a notable diffusion in southern Italy and possible external influences on its consolidation.