S.C. Code Ann. § 12-37-714 — Boats with situs in State; boat or motor under contract for repairs

In addition to any other provisions of law subjecting boats and boat motors to property tax in this State:
(1) A boat, including its motor if separately taxed, used in interstate commerce having a tax situs in this State and at least one other state is subject to property tax in this State. The value of such a boat must be determined based on the fair market value of the boat multiplied by a fraction representing the number of days present in this State. The fraction is determined by dividing the number of days the boat was present in this State by three hundred sixty-five days. A boat used in interstate commerce must be physically present in this State for thirty days in the aggregate in a property tax year to become subject to ad valorem taxation.
(2) A boat, including its motor if the motor is separately taxed, which is not currently taxed in this State and is not used exclusively in interstate commerce, is subject to property tax in this State if it is present within this State for sixty consecutive days or for ninety days in the aggregate in a property tax year. Upon an ordinance passed by the local governing body, a county may subject a boat, including its motor if the motor is separately taxed, to property tax if it is within this State for ninety days in the aggregate, regardless of the number of consecutive days. Also, upon an ordinance passed by the local governing body, a county may increase the number of days in the aggregate a boat, including its motor if the motor is taxed separately, must be in this State to be subject to property tax to one hundred eighty days in a property tax year, regardless of the number of consecutive days. Upon written request by a tax official, the owner must provide documentation or logs relating to the whereabouts of the boat in question. Failure to produce requested documents creates a rebuttable presumption that the boat in question is taxable within this State.
(3) When a boat, or motor if separately taxed, is subject to a written contract for repairs and located in a marine repair facility in this State, the time periods provided pursuant to items (1) and (2) of this section are tolled.