South Dakota business tax extension
South Dakota has no corporate income tax. South Dakota taxes financial institutions through a bank franchise tax. The federal extension is Form 7004, due for calendar-year corporations and for partnerships and S corporations. In general, an extension gives you more time to file, not more time to pay.
Last updated · From South Dakota's own forms, instructions and laws, cited below
Does South Dakota have a corporate income tax?
No. South Dakota has no corporate income tax.South Dakota taxes financial institutions through a bank franchise tax. Your federal return still needs its own federal extension.
South Dakota's rules for each return, as its own instructions and laws state them:
Bank franchise tax (financial institutions only)
- Return
- Bank franchise tax return, filed through the Department's online Filing and Payment portal
- Due date
- 15 days after the financial institution's federal income tax return is due
- Extension
- The return is extended only if the federal extension is filed and, by the original bank franchise due date, the Department receives a cover letter asking for the extension, a copy of the federal extension request, and the estimated tax. Email the letter and federal request to [email protected], not through the online portal.
- Extension length
- 6 months
- Extended due date
- Six months after the original bank franchise tax due date
- Payment
- The tax is due by the original due date, even with an extension. To pay with the extension: through the online Filing and Payment portal, with or before the extension request.
When is the federal business extension due?
Corporations, S corporations, partnerships, multi-member LLCs, estates and trusts extend their federal return with Form 7004, filed by the return's original due date. The extension is automatic: no reason is needed and the IRS doesn't approve it. We e-file it for a flat $9.95. These are the 2027 dates for calendar-year 2026 returns:
| Return | Who files | File the extension by | Extended to |
|---|---|---|---|
| Form 1065 Partnerships & multi-member LLCs, Form 7004 | 6 months | ||
| Form 1120-S S corporations (and LLCs taxed as S corps), Form 7004 | 6 months | ||
| Form 1120 C corporations (and LLCs taxed as C corps), Form 7004 | 6 months | ||
| Form 1041 Estates & trusts, Form 7004 | 5½ months | ||
| Form 990, 990-EZ, 990-PF Tax-exempt organizations & private foundations, Form 8868 | May 15, 2027 is a Saturday | 6 months |
Federal dates follow the IRS rule: a deadline on a weekend or legal holiday moves to the next business day. A fiscal-year business counts from its own year-end; see the fiscal-year deadline guide.
Tax-exempt organizations extend the 990 series with Form 8868, not Form 7004. Each return needs its own extension, so extending a business return does not extend its owners' personal returns.
Does an extension give more time to pay?
No. A federal extension moves the filing deadline only: tax owed is due by the original due date, and the IRS charges interest and the late-payment penalty on anything paid after it. South Dakota's instructions say the same for its returns: a South Dakota extension doesn't move the payment deadline. More in does an extension give you more time to pay?
Where are South Dakota's forms and instructions?
On the South Dakota Department of Revenue website, which has the current forms, instructions and online services. The rules on this page are summarized from the sources below. We e-file the federal extension; the South Dakota return and any South Dakota extension request go to the state.
South Dakota extension FAQ
Does South Dakota have a corporate income tax?
No. South Dakota taxes financial institutions through a bank franchise tax. A federal return still needs a federal extension: Form 7004 for a business, filed by the return's original due date.
When is the South Dakota Bank franchise tax return due?
15 days after the financial institution's federal income tax return is due.
Does a South Dakota extension give more time to pay?
No. The tax is due by the original due date, even with an extension. To pay with the extension: through the online Filing and Payment portal, with or before the extension request.
Does a South Dakota business still need a federal extension?
Yes, to get more time for its federal return: Form 7004, filed by April 15, 2027 for a calendar-year corporation or March 15, 2027 for a partnership or S corporation.
Sources
- Taxes (Businesses) - South Dakota Department of Revenue, read
- Bank Franchise Tax - South Dakota Department of Revenue, read
- SDLRC - Codified Law 10-43-30 - Time for filing annual return and paying tax--Penalty and interest for delinquency, read
- SDLRC - Codified Law 10-43-30.1 - Extension of time to file return--Conditions--Interest, read
Filing a federal business extension this season?
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