South Carolina Filing Due Date: SC individual income tax returns are due by April 15, in most years — or by the 15^th day of the 4^th 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 from April 15 to October 15 (for calendar year filers).

South Carolina Tax Extension Form: To request a South Carolina extension, file Form SC4868 by the original due date of your return. Make sure to attach a copy of your extension to your South Carolina tax return when you file.

If you have an approved Federal tax extension (IRS Form 4868) and you’re due a South Carolina tax refund, you will automatically be granted a South Carolina extension. In this case, you do not need to file Form SC4868. Remember to attach a copy of your Federal extension to your South Carolina tax return when it’s filed.

South Carolina Extension Payment Requirement: A tax extension gives you extra time to file. It does not give you more time to pay your South Carolina income tax. All state tax payments are due by the original deadline of the return (April 15 for most). Any SC tax that hasn’t been paid by the proper due date will be subject to interest and penalties. Furthermore, at least 90% of your South Carolina tax liability must be paid on time in order to get a state extension. You can make a South Carolina extension payment using Form SC4868, or with a copy of your Federal extension (IRS Form 4868) that’s marked “For South Carolina.”