A computer device may include logic configured to receive a Session Initiation Protocol (SIP) telephone call and identify the SIP telephone call as originating from a first toll-free telephone number and destined for a second toll-free telephone number. The computer device may further determine a screened telephone number associated with the first toll-free telephone number; generate a diversion header that includes the determined screened telephone number for the SIP telephone call, in response to identifying the SIP telephone call as originating from the first toll-free telephone number and destined for the second toll-free telephone number; and send the SIP telephone call to a local exchange carrier network associated with the second toll-free telephone number.