South Carolina State Income Tax Overview

The South Carolina Department of Revenue governs the levying of individual income tax laws for the state of South Carolina and the collection of state income tax under those laws.  South Carolina state income tax laws are similar in structure to federal income laws but with some modifications.

South Carolina state income tax requires the filing of a separate tax return from that filed with the Internal Revenue Service (IRS) for federal income tax purposes.

Following are frequently asked questions about South Carolina state income tax, such as who has to file, tax rates, and due dates for any tax owed.  If you have additional questions about filing federal income tax, visit our “Tax Relief” page.

Who has to file a South Carolina state income tax return?

If you earn income in South Carolina and you are required to file a federal income tax return for a given tax year, then you must also file a state income tax return for South Carolina.

If you lived in South Carolina for only a portion of the tax year, you can choose to be considered a full-year resident or a non-resident for tax purposes, whichever is more beneficial to you as the taxpayer.  As a full-year resident, you are taxed by South Carolina on all income earned regardless of what state the income source is based in, but you are allowed to deduct any amount paid to other states for state income tax purposes.

As a non-resident, you are taxed by South Carolina on only the income earned from sources based in South Carolina, and you cannot therefore deduct any taxes paid to other states.

If you are not required to file a federal income tax return but you had taxes withheld from your wages that you want to recover, you must likewise file a state income tax return to recoup those tax withholding dollars.

How does South Carolina calculate the tax that I owe?

South Carolina makes use of a graduated tax rate that ranges from a low of 0% to a high of 7% as your taxable income increases.

When is my South Carolina state income tax return due each year?

South Carolina state income taxes are due by April 15 following the tax year.  When April 15 falls on a non-business day, taxes are due on the first business day thereafter.

Taxpayers may obtain a six-month extension on the time to file by submitting form SC4868.  This form allows for an extension of filing only, not for an extension of paying any tax liability due.  If an estimated payment of taxes due is not still made by April 15, you may be charged both penalties and interest related to the unpaid balance.

How can I get help with my South Carolina state income taxes?

If you need help completing your state income tax return for one or more years or you just have questions about how financial or life decisions will affect your income tax, you can get the help you need by calling the telephone number at the top of this page.  A tax attorney who knows the tax laws of South Carolina as well as at the federal level can work with you to be sure all of your questions are answered and to help you file your state and federal income tax returns.

by Mark Johnston

Mark has been a contributor to legal web sites related to bankruptcy, tax, and criminal law since 2011. He has an Accounting degree from Texas A&M University.