The present disclosure discloses a method, an apparatus, and a system for providing a specified communications service, and a terminal, and belongs to the field of network technologies. The method includes: sending a specified communications service request to a signaling access server, the specified communications service request carrying a third-party application identifier and a first user identity of a local end, and the signaling access server being configured to provide a specified communications access service; if verification on the third-party application identifier and the first user identity is successful, establishing a signaling path to the signaling access server, the signaling path being configured to provide a signaling transmission interface to the signaling access server; and performing specified communication based on the signaling path.