A method implemented by a terminal for accessing a CSG femtocell of a first access network. The terminal includes a list containing identifiers of CSG femtocells to which an access right is defined. The method includes: scanning a frequency band for discovering CSG femtocells; decoding, based on a key, a data stream broadcasted from the CGS femtocells; obtaining, based on the decoded data stream, an identifier of the CSG femtocells; and determining, based on the list, whether the terminal has authorised access to the discovered femtocells. The frequency band, the key or the list is determined based on a message received from a remote server via a second cellular access network different from the first access network.