Baélls (also spelled Baells) is a municipality in the province of Huesca, in the autonomous community of Aragon, Spain. It is located in the northeastern part of the country, within the comarca of La Litera in the eastern reaches of Huesca province.
The municipality is small and sparsely populated. According to the 2004 census carried out by the Instituto Nacional de Estadística (INE), Baélls had a population of 134 inhabitants. That figure reflects the pattern of rural depopulation seen across much of inland Aragon, where many municipalities of similar size have seen their populations decline over the twentieth century.
As a municipality, Baélls holds the basic administrative status granted to recognised local entities in Spain, with its own local government. Its name appears in official records in both the accented form Baélls and the unaccented form Baells.