South Carolina Business Tax Extension 2026: 2025 Tax-Year Filing Guide
LLC & Partnership · S Corporation · C Corporation · Fiduciary
This guide explains how to file a South Carolina (SC) business tax extension for each entity type. For example, CBT taxpayers generally receive six months, while partnerships generally receive five months. However, estimated tax remains due by the original deadline.
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Remember, payment is still due by the original deadline. In other words, extensions only extend filing time.
South Carolina (SC) rules depend on entity type. Next, confirm the entity’s classification, file the required extension or retain federal proof when applicable, and pay required tax by the original deadline.
South Carolina LLC Tax Extension: Filing Details
A calendar-year partnership or LLC taxed as a partnership generally files Forms SC1065, as applicable, when a South Carolina filing obligation applies. For the 2025 calendar-year return, the extended filing deadline is September 15, 2026.
In addition, the extension applies to filing time only. Therefore, pay required South Carolina tax by the original deadline to limit penalties and interest.
The extension applies to filing time only. Pay required South Carolina tax by the original deadline to limit penalties and interest.
South Carolina S Corporation Tax Extension: Filing Details
For an S corporation, a calendar-year business generally files Form SC1120S when it has a South Carolina filing obligation. For the 2025 calendar-year return, the extended filing deadline is October 15, 2026.
South Carolina C Corporation Tax Extension: Filing Details
For a C corporation, a calendar-year business generally files Form SC1120 and must follow South Carolina corporate-income-tax extension rules. For the 2025 calendar-year return, the extended filing deadline is October 15, 2026.
The extension applies to filing time only. Pay required South Carolina tax by the original deadline to limit penalties and interest.
The extension applies to filing time only. Pay required South Carolina tax by the original deadline to limit penalties and interest.
Fiduciary, Estate, and Trust Filing Details
Finally, a calendar-year estate or trust generally files Form SC-1041 when it has a South Carolina fiduciary filing obligation. For the 2025 calendar-year return, the extended filing deadline is October 15, 2026.
Quick Reference: Deadlines and Forms
The table below provides a quick reference to South Carolina business tax extensions. See our IRS Form 7004 guide, South Carolina individual tax extension, and business tax extension resource for related guidance.
| Entity Type | SC Return Form | Extension Method | Extended Deadline |
|---|---|---|---|
| LLC / Partnership | SC1065 / SC1065 | Federal 5-month; SC8736 / SC1120T | Sept. 15, 2026 |
| S Corporation | SC1120S | SC1120T | Oct. 15, 2026 |
| C Corporation | SC1120 / SC1120 | SC1120T | Oct. 15, 2026 |
| Fiduciary / Estate / Trust | SC-1041 | Form SC-630 | Oct. 15, 2026 |
Frequently Asked Questions
Quick answers about South Carolina business tax extensions – but always confirm the current rules with the South Carolina Division of Taxation.
Visit SC DORYes. However, the applicable entity-specific requirements listed above must be satisfied. South Carolina grants extensions to LLCs, partnerships, S corporations, C corporations, and fiduciaries, but the rules – including which form to file, how long the extension lasts, and the payment threshold – vary by entity type.
Generally no. In other words, pay required tax by the original deadline and confirm the current state payment rules. An extension of time to file does not extend the time to pay – failing to pay by the original deadline can result in penalties and interest, even if the return is filed within the extended window.
No. In practice, partnerships, S corporations, C corporations, and fiduciaries can use different original dates, extension periods, or forms. For 2025 calendar-year returns filed in 2026, partnerships and LLCs taxed as partnerships get a five-month extension (Sept. 15), while the others generally get a six-month extension (Oct. 15).
Review the South Carolina Division of Taxation guidance for the entity’s return. Additionally, the DOR publishes the most current forms (SC1120T, SC8736, SC-630, etc.) and any changes to extension periods or payment thresholds.
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