South Carolina taxable income of a partnership is the same as for federal partnership income tax purposes with certain South Carolina modifications. Taxable income (loss) of a partnership flows through and is taxable to the partners in the same manner as for federal partnership income purposes. Multi-state partnerships determine South Carolina taxable income by applying an apportionment ratio to the various income (loss) amounts of the partnership. Partnerships manufacturing or dealing with tangible personal property use a four factor apportionment ratio of property, payroll and sales counted twice. Others use a single factor apportionment ratio. Real estate gains (losses) and dividends, however, are allocated to the state of situs or state of partner domicile, respectively. Federal taxable income items apportioned or allocated to South Carolina and taxable to nonresident partners are subject to withholding by the partnership at a five percent rate. Nonresident partners providing affidavits of their intention to file and partnerships filing a composite return on behalf of all of their nonresident partners are exempt from the withholding requirement.
Payment of withholding tax is due along with the filing of the return by the fifteenth day of the fourth month after year end.