Mississippi Business Tax Deadlines (2026)
Next: June 15, 2026 — Federal & Mississippi Q2 Estimated Tax Payment
Next Deadline: June 15, 2026 — Federal & Mississippi Q2 Estimated Tax Payment
Federal Tax Deadlines (2026)
| Form | Who Files | Due Date | Extension Deadline |
|---|---|---|---|
| Form 1040 (Schedule C) | Sole proprietors | April 15 | October 15 |
| Form 1065 | Partnerships, Multi-member LLCs | March 15 | September 15 |
| Form 1120-S | S-Corporations | March 15 | September 15 |
| Form 1120 | C-Corporations | April 15 | October 15 |
| Form 990 | Nonprofits | May 15 | November 15 |
| Estimated Taxes (Q1) | All | April 15 | — |
| Estimated Taxes (Q2) | All | June 15 | — |
| Estimated Taxes (Q3) | All | September 15 | — |
| Estimated Taxes (Q4) | All | January 15, 2027 | — |
Mississippi State Tax Deadlines (2026)
| Tax Type | Due Date | Form/Filing | Notes |
|---|---|---|---|
| Individual Income Tax | April 15 | Form 80-105 | Flat 4.7% (first $10K exempt) |
| Corporate Income Tax | March 15 | Form 83-105 | Rates 3%–5% |
| S-Corp Return | March 15 | Form 84-105 | Pass-through |
| Partnership Return | March 15 | Form 86-105 | Pass-through |
| Corporate Franchise Tax | March 15 | Filed with Form 83-105 | $2.50 per $1,000 of capital |
| Sales Tax (Monthly) | 20th of following month | Via TAP | State rate 7% |
| Withholding Tax (Monthly/Quarterly) | 15th of following month | Via TAP | Employers |
| Annual Report | April 15 | Filed with Secretary of State | $25 fee |
| Estimated Income Tax (Q1) | April 15 | Form 80-106 / 83-300 | — |
| Estimated Income Tax (Q2) | June 15 | Form 80-106 / 83-300 | — |
| Estimated Income Tax (Q3) | September 15 | Form 80-106 / 83-300 | — |
| Estimated Income Tax (Q4) | January 15, 2027 | Form 80-106 / 83-300 | — |
Quarterly Estimated Tax Deadlines in Mississippi
Mississippi follows the federal estimated tax payment schedule:
Estimated payments are required if you expect to owe $200 or more in Mississippi income tax.
Mississippi-Specific Tax Requirements
Mississippi has moved toward a flat individual income tax rate of 4.7%, with the first $10,000 of income exempt (effectively creating a 0% bracket for low earners). The corporate income tax has graduated rates: 3% on the first $5,000, 4% on $5,001–$10,000, and 5% on income over $10,000. Mississippi also levies a corporate franchise tax of $2.50 per $1,000 of capital invested in the state, with a minimum of $25.
Mississippi's state sales tax rate is 7%, one of the highest in the nation, with no additional local sales taxes in most areas. Groceries are taxed at a reduced rate of 5%. The economic nexus threshold for remote sellers is $250,000 in sales. Businesses file sales tax through the Taxpayer Access Point (TAP).
Note that Mississippi corporate income tax and franchise tax returns are due March 15 (the 15th day of the 3rd month), which is earlier than many states. Annual reports are due April 15 and filed with the Secretary of State for a $25 fee. Mississippi requires employer withholding with filing frequency based on payroll amounts.
What Happens If You Miss a Mississippi Tax Deadline?
Mississippi Department of Revenue
Get Your Books Ready Before Tax Season
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