Methods, systems, and computer program products for communicating CNAM services for SIP originated calls terminating in a circuit switched network is described. In one embodiment, the method includes, at a SIP-SS7 gateway, receiving a SIP call setup message that includes a SIP calling subscriber identifier information, associating a temporary telephone number with the SIP calling subscriber identifier information, generating an SS7 call setup message associated with the SIP call setup message, wherein the SS7 call setup message includes the temporary telephone number, and communicating the temporary telephone number and SIP calling subscriber identifier information to a calling name interworking function (CIF) module. The method also includes, at the CIF module, storing the temporary telephone number and the associated SIP calling subscriber identifier information in a local cache, receiving a CNAM query message containing the temporary telephone number from a terminating switching office, and transmitting a CNAM response message to the terminating switching office including the SIP calling subscriber identifier information.