S.C. Code Ann. § 40-2-245
(A) An individual whose principal place of business is outside this State is presumed to have qualifications substantially equivalent to this state's requirements and may exercise all the privileges of licensees of this State without the need to obtain a license under Section 40-2-35 if the individual:
(1) holds a valid license as a certified public accountant from any state which requires, as a condition of licensure, that an individual:
(C) An individual licensee or holder of a permit to practice in another state exercising the privilege afforded under this section and the firm that employs that licensee simultaneously consents, as a condition of exercising this privilege:
(D) An individual who qualifies for practice privileges under this section who performs any of the following services for an entity with its home office in this State may only perform these services through a firm that has obtained a registration issued under Section 40-2-40: