S.C. Code Ann. § 42-9-230: Date on which compensation payable under agreement becomes due.

The first installment of compensation payable under the terms of an agreement is due on the fourteenth day after the employer has knowledge of the injury or death, on which date all compensation due must be paid. Thereafter, compensation must be paid in installments weekly, except when the commission determines that payment in installments should be made monthly or at some other period.

Installments paid weekly must be paid on the same day of the week, installments paid monthly must be paid on the same day of the month, and installments paid on some period other than weekly or monthly must be paid on the same day of each period.