S.C. Code Ann. § 58-9-520

Whenever a telephone utility desires to put into operation a new rate or tariff which affects the telephone utility's general body of subscribers, the telephone utility shall give the commission and the Office of Regulatory Staff not less than thirty days' notice of its intention to file and shall, after the expiration of the notice period, then file with the commission and provide to the Office of Regulatory Staff a schedule setting forth the proposed changes; provided, however, a hearing shall not be required when the proposed rate or tariff is a proposal to institute or modify an offering or regulation that is not part of a general rate case and does not affect the telephone utility's general body of subscribers. Subject to the provisions of subsections (B) and (C) of Section 58-9-540, the proposed changes must not be put into effect in full or in part until approved by the commission.