South Carolina Filing Due Date: Corporation tax returns are due by March 15 — or by the 15th day of the 3rd month following the end of the taxable year (for fiscal year filers).
Extended Deadline with South Carolina Tax Extension: South Carolina offers a 6-month extension, which moves the filing deadline to September 15 (for calendar year filers).
South Carolina Tax Extension Form: If any South Carolina tax is due, an extension can be requested by filing Form SC1120-T on or before the original deadline of your return. If zero South Carolina tax is due and you have a valid Federal extension (IRS Form 7004), you will automatically be granted a corresponding South Carolina extension for the same amount of time. Make sure to attach a copy of your approved extension (Federal or South Carolina) to your state tax return when you file.
South Carolina Extension Payment Requirement: An extension of time to file is not an extension of time to pay. If you owe South Carolina tax, it must be paid by the original due date, or penalties and interest will be charged. You can make an extension payment using Form SC1120-T, or file and pay electronically through South Carolina’s Electronic Payment System: www3.sctax.org/DOREPAY