S.C. Code Ann. § 59-53-500: Tax exemption; interest on bonds.

In performing an essential governmental function in the exercise of the powers conferred upon it, the authority is not required to pay taxes or assessments upon property or upon its activities or operations or the income from them, or taxes or assessments upon property acquired or used by the authority or upon the income from them. Bonds, notes, or other obligations or indebtedness issued by the authority, and the income from them, are free from taxation and assessment of every kind by the State and by the local governments and other political subdivisions of the State.