South Carolina Income Tax and Withholding

Periodic Returns. Quarterly Form WH-1605 must be filed by the end of the month following the quarter, for the first three quarters. The form for the last quarter is due by the last day of February. Withheld taxes must be deposited at the same time as federal taxes, using Form WH-1601.

Annual Reconciliation Returns. Form WH-1606 due by the last day of February.

Timely Filing. When the due date for returns and reports falls on a Saturday, Sunday, or legal holiday, such reports shall be deemed timely filed if postmarked the following day. Returns and reports are deemed timely filed if postmarked the day due.