S.C. Code Ann. § 12-37-135

A county governing body may require a business registration throughout the entire county area and may impose an administrative fee not to exceed fifteen dollars. The fee is an administrative fee and must not be based upon business income. The business registration authorized by this section must be administered and enforced in the same manner as the business license tax described in Section 4-9-30(12), but must not be converted into a business license tax as described in that provision. The business registration administrative fee may be billed on any property tax bill and is deemed to be property tax for the purposes of collection if so billed. This registration, if adopted, is in lieu of any business license which is authorized pursuant to Section 4-9-30(12).