South Carolina Code 36-9-631. Posting and mailing notice of sale
(2) In addition to the posting of notice required by subsection 91), the secured party or other party holding a public sale shall, at least five days before the date of sale, mail by registered or certified mail a copy of the notice of sale to each debtor obligated under the security agreement:
(a) At the actual address of the debtors, if known to the secured party, or
(b) At the address, if any, furnished the secured party, in writing, by the debtors, or otherwise at the last known address.
(c) In the case of consumer goods, no other notification need be sent. In other cases, in addition to mailing a copy of the notice of sale to each debtor, the secured party shall also mail a copy of such notice by registered or certified mail to any other secured party from whom the secured party has received (before sending the notice of sale to the debtor) written notice of a claim or an interest in the collateral.
(4) The time for the posting of the notice of sale and the mailing of the notice required by this section shall be computed so as to exclude the first day of posting and mailing and to include the day on which the sale is to occur.