Administration of the North American Numbering Plan, Carrier Identification Codes (CICs)
On April 11, 1997, the Commission released a Second Report and Order setting January 1, 1998, as the end for the transition, or permissive dialing period, for the expansion from three digit to four digit Feature Group D carrier identification codes (CICs), and modifying the CIC conservation plan to allow for up to two CICs per entity. The Second Report and Order is intended to alert the industry and the general public that after January 1, 1998, only four digit CICs, and the corresponding seven digit carrier identification codes (CACs), will be recognized.