Cossato is a municipality in the province of Biella, Italy, in the northwest part of Piedmont, 11.6 kilometres (7.2 mi) east of Biella. It has a population of ca 14.826 and it spreads over an area of 27,74 km², being the second town in order of size and importance in the Province of Biella. It is crossed by the Strona di Mosso stream.