The city of Castelo Branco is a municipality and former bishopric in Castelo Branco District, in Centro Region, Portugal. The name means "white castle".
The city of Castelo Branco is made up of one Freguesia (civil parish) with a population of 30,649 in 2001. The municipality has a total of 19 parishes. The population in 2011 was 56,109, in an area of 1,438.19 square kilometres (555.29 square miles), making it one of the largest municipalities in Portugal.