Mississippi estimated tax due dates for 2026
Mississippi estimated income tax payments for tax year 2026 are due April 15, 2026, June 15, 2026, September 15, 2026, January 15, 2027. That matches the federal schedule. Below: who has to pay, how to avoid an underpayment penalty and where to pay, with the official source.
| Payment | Mississippi due date |
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| 1 | |
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Federal 2026 estimated tax due dates, for comparison: April 15, 2026, June 15, 2026, September 15, 2026, January 15, 2027.
Who must pay Mississippi estimated tax?
Every individual taxpayer who does not have at least eighty percent (80%) of his/her annual tax liability prepaid through withholding must make estimated tax payments if his/her annual tax liability exceeds two hundred dollars ($200).
How do you avoid a Mississippi underpayment penalty?
Estimated tax payments (plus withholding) must not be less than 80% of the annual income tax liability; underestimates or late payments incur interest of 1/2% per month. A prior-year-tax safe harbor was not confirmed on the DOR page (see Form 80-320 for exceptions).
How much should you pay?
Start with your federal estimate: the free Quarterly Estimated Tax Calculator works out your 2026 federal payments and safe harbor. Mississippi figures its own tax, so the state amount is separate.
