The surname Serrato may be interpreted within the wide group of surnames derived from the term serra, a Latin word that alludes both to the saw (a tool for cutting) and to a mountainous elevation. In this sense, it could have an occupational origin, linked to the trade of the sawyer —a form clearly preserved in the variant Serratore—, or else a toponymic origin, indicating provenance from a place called Serra or characterized by mountainous terrain. A descriptive interpretation is also possible, since in Italian serrato means "closed," "compact" or "narrow," which could have functioned as a nickname. Among the related variants are Serratore, Serratori, Serrati, Serrato and eventually simplified forms arisen through dialect evolution or migratory adaptation. In contexts of southern Italy, especially in Calabria, the variant Serratore appears clearly documented, which suggests a possible historical relation between these forms.

• Serrato → Present in southern Italy; possible concentration in Calabria. There also exists the place name Serrato in the province of Vibo Valentia (Calabria).

• Serratore → Typically Calabrian; documented in several provinces of Calabria (Catanzaro, Vibo Valentia).

• Serratori → A patronymic/plural variant, present in the centre-north of Italy, especially in Emilia-Romagna and Lombardy.

• Serrati → More diffused in the north and centre of Italy; records in Lombardy and Tuscany.

• Serra (related base form) → Very widespread throughout Italy, with a strong presence in Piedmont, Liguria and Sardinia.