S.C. Code Ann. § 12-2-75 – Signatories to tax returns

(A) Returns filed by taxpayers with the department must be signed by the following:
1. (1) corporate returns by an authorized officer of the corporation;
2. (2) partnership returns by its manager or an authorized general partner of the partnership;
3. (3) trust and estate returns by the trustee, personal representative, executor, or administrator, whichever is applicable;
4. (4)
  1. (a) except as provided in subitems (b) and (c), individual returns must be signed by the individual;
  2. (b) deceased individual returns for individuals who would have been required to file a state tax return while living by the personal representative, administrator, or executor of the decedent's estate and the tax must be levied upon and collected from the estate;
  3. (c) if an individual is unable to make a return or payment, including an estimated tax payment, it must be made by an authorized agent, a guardian, or other person charged with the conduct of the business of the taxpayer;
5. (5) returns for any other person by an authorized officer or owner.
(B) In the instructions to a return, or otherwise, the department may authorize taxpayers to sign returns by other means, including electronically, and may authorize the signature to be filed or deposited with and be kept or forwarded by a third party. To the extent that a tax return preparer, as that term is defined in Internal Revenue Code Section 7701(a)(36), is required or permitted to sign a return, the department in the instructions to a return, or otherwise, may authorize the tax return preparer to sign the return by other means, including electronically.