The copy of the withholding statement furnished to the employee by the employer, as required under Section 12-8-1540, designated for attachment to the employee's income tax return, must be attached to the income tax return of the employee if the employee files a paper return. A copy of Form 1099 or other information return reflecting South Carolina withholding must be attached to the income tax return of the taxpayer if the taxpayer files a paper return. Failure to comply may result in the disallowance of the withholding claimed.
S.C. Code Regs. § 117-855.1