A session management function (SMF) receives, from a wireless device, a first message requesting establishment of a PDU session for a network slice associated with a service of a communication service provider (CSP). The first message comprises a single network slice selection assistance information (S-NSSAI) of the network slice and a CSP identifier (ID). The SMF sends, to the wireless device, a second message accepting the establishment of the PDU session for the network slice associated with the service of the CSP.