S.C. Code Ann. § 63-17-3520
(C) Except as otherwise provided in subsection (D) and Section 63-17-3530, the employer shall withhold and distribute the funds as directed in the withholding order by complying with terms of the order which specify:
(D) An employer shall comply with the law of the state of the obligor's principal place of employment for withholding from income with respect to: