Cerreto Castello was a comune (municipality) in the Province of Biella in the Italian region Piedmont, located about northeast of Turin and about east of Biella. As of 31 December 2004, it had a population of 662 and an area of .
As a comune Cerreto Castello bordered the following municipalities: Cossato, Quaregna, Valdengo, Vigliano Biellese.
From 1 January 2019 Cerrato Castello was absorbed by the new-born municipality of Quaregna Cerreto.