SC990-T: Exempt Organization Business Tax Return (Revision 2023-06)
South Carolina · South Carolina DOR · Used for tax years 2024, 2025, 2026
Form SC990-T is South Carolina’s Exempt Organization Business Tax Return. It reports federal unrelated business taxable income, South Carolina adjustments, credits, and payments to calculate the tax balance due or overpayment.
Who files this form
In general, every corporation or unincorporated entity operating in South Carolina that must file federal Form 990-T to report unrelated business income must also file SC990-T.
Only multi-state organizations must complete Schedules F, G, and H.
When it's due
For tax years 2024, 2025, and 2026, file SC990-T by the 15th day of the fifth month after the end of the tax year.
An extension gives you more time to file, but not more time to pay. Pay any tax due by the original due date to avoid late penalties and interest.
If no tax is due and you requested a federal extension, South Carolina accepts that extension if your SC990-T is received within the time extended by the IRS.
What you'll need
- A complete copy of your federal Form 990-T and supporting schedules, which you must attach to SC990-T.
- Forms 1099 or I-290, if reporting tax withheld on line 10a.
- SC1120TC and tax credit schedules, if claiming credits.
- Schedules explaining other additions or deductions, if reporting those items in Schedule A and B.
- SC2220, if your organization underpaid Estimated Tax.
You will also need your organization's FEIN, tax period, address, and payment amounts, including payments made by declaration or with an extension.
How to file
Complete SC990-T using federal unrelated business taxable income as the starting point, with the required South Carolina adjustments. Attach your complete federal return and supporting schedules, and have an officer sign the return.
Mail your return
Balance due returns:
SCDOR Corporate Taxable
PO Box 100151
Columbia, SC 29202
Refund or zero tax returns:
SCDOR Corporate Refund
PO Box 125
Columbia, SC 29214-0032
Pay your balance
Pay online through MyDORWAY at dor.sc.gov/pay. Select Business Income Tax Payment.
If paying by check, make it payable to SCDOR and include your name, FEIN, tax year, and SC990-T in the memo. Do not send cash.
Request a filing extension
Paying your balance due through MyDORWAY automatically submits your filing extension request. No additional form or paperwork is required. To request an extension by mail, use SC1120-T, available at dor.sc.gov/forms.
The provided text gives online payment and extension options, but does not describe electronic filing of SC990-T.
Common mistakes
- Forgetting the federal return. Attach a complete copy of federal Form 990-T and its supporting schedules.
- Treating a filing extension as a payment extension. There is no extension of time to pay. Late payment can result in penalties and interest.
- Leaving the extension box unchecked. Mark it if you filed a federal or state extension.
- Missing the filing deadline. Failure to file on time, including any extension, can result in a penalty.
- Omitting SC2220 after underpaying Estimated Tax. Complete and attach it. If a penalty is owed and you are due a refund, subtract the penalty from the overpayment on line 15.
- Sending cash or an incomplete check memo. Do not send cash. Include your name, FEIN, tax year, and SC990-T in the check memo.
- Overlooking closure requirements on a final return. You must close with both the South Carolina Secretary of State and SCDOR.
Questions people ask
What tax rate does SC990-T use?
Line 7 calculates tax by multiplying South Carolina net income subject to tax on line 6 by 5%.
Can my organization deduct a South Carolina net operating loss?
Line 5 allows the South Carolina net operating loss carryover that can be deducted in the current tax year. To be deductible, the loss must have been incurred in an unrelated trade or business activity. The instructions direct you to add back the federal net operating loss in Schedule A before subtracting the South Carolina loss on line 5.
What can I do with an overpayment?
Line 15 lets you apply an overpayment to Estimated Tax or request a refund.
Where can I calculate penalties and interest?
Use the Penalty and Interest Calculator at dor.sc.gov/calculator.