The Ñuble Region is one of the sixteen regions in which Chile is administratively divided. With a total area of 13 178.5 km² and administratively constituted by 3 provinces and 21 communes, Ñuble has a population of 480 609. Its capital is the city of Chillán. The region limits to the north with the provinces of Linares and Cauquenes, of the Maule Region. To the southwest with the province of Concepción and to the south with the province of Biobío, both of the Biobío Region. To the east with the province of Neuquén of Argentina and to the west with the Pacific Ocean.
Its main urban center is the Gran Chillán, made up of the homonymous city and the adjoining urbanization that add 215 646 inhabitants, followed in second place by San Carlos with 53 024 inhabitants. On August 19,2017, President Michelle Bachelet signed the decree promulgatory of the law that created the Ñuble Region, separating it from the Biobío Region, which was published in the Official Gazette on September 5,2017, entering valid one year later, on September 6,2018.