Systems and methods for controlling features and services in packet-based networks are disclosed. The present application provides systems and methods that include sending a first message to a network core device, and identifying a profile from user account information stored on the network core device. The profile specifies which features and services may or may not be implemented by an end device. In the systems and methods of the present application, the profile is added to a second message that is sent from the network core device to the end device. Alternatively, a single message or multiple messages containing the profile, regardless and/or independent of any prior message sent from an end device, may be sent from the network core device to the end device. These systems and methods may also use the session initiation protocol for their communications, with the end devices being session initiation protocol phones and the network core device being a session initiation server.