S.C. Code § 58-5-270
Applications may be made by any corporation, public or private, person, chamber of commerce or board of trade, by any civic, commercial, mercantile, traffic, agricultural, or manufacturing association or by any body politic, commission, board, or municipal corporation by petition in writing, setting forth any act or thing done, or omitted to be done, with respect to which, under the provisions of Articles 1, 3, and 5 of this chapter, the commission has jurisdiction or is alleged to have jurisdiction. Individual consumer complaints must be filed with the Office of Regulatory Staff which has the responsibility of mediating consumer complaints under the provisions of Articles 1, 3, and 5. If a complaint is not resolved to the satisfaction of the complainant, the complainant may request a hearing before the commission. The commission has jurisdiction to hear complaints regarding the reasonableness of any rates or charges that affect the general body of ratepayers; but the commission may at its discretion refuse to entertain a petition as to the reasonableness of any rates or charges unless it be signed by the mayor or the president or chairman of the board of trustees or a majority of the council, commission or other legislative body of the city or county or city or town affected by the subject matter of such complaint or by not less than twenty-five consumers of the public utility named in the complaint. Any public utility shall have the right to petition the commission on any of the grounds upon which petitions are allowed to be filed by other parties, including the fairness, reasonableness, or sufficiency of any schedule, classification, rate, price, charge, fare, toll, rental, rule, regulation, service, or facility of such public utility and in such event the same procedure shall be adopted and followed as in other cases.
S.C. Code § 58-5-270