Crosa is a frazione of the comune of Lessona , in the Province of Biella in the Italian region Piedmont , located about 70 kilometres (43 mi) northeast of Turin and about 12 kilometres (7 mi) northeast of Biella. As of 31 December 2004, it had a population of 332 and an area of 1.0 square kilometre (0.39 sq mi). From 1 January 2016 Crosa was absorbed by the neighbouring municipality of Lessona.

As an autonomous comune Crosa bordered the following municipalities: Casapinta , Cossato , Lessona, Strona .