Crucial 2026 MS Tax Filing Deadlines: Essential Dates to Remember

Jordan Hartwell

Published: February 5, 2026 10:08 PM ET

Tax deadlines are vital for residents of Mississippi, especially as the 2026 tax season approaches. Knowing the essential dates for filing can alleviate stress and help ensure compliance.

Crucial 2026 MS Tax Filing Deadlines

Filing and Payment Deadline

The deadline to file and pay federal and state taxes in Mississippi for the 2025 tax year is Wednesday, April 15, 2026. It is important to adhere to this date, as it is recognized by both the Internal Revenue Service (IRS) and the Mississippi Department of Revenue.

Mail Filings

If you opt to file your tax return by mail, ensure that your envelope is properly addressed and postmarked by the filing deadline. This attention to detail is crucial for the IRS to consider your return “on time.”

Extensions and Disaster Relief

In certain situations, taxpayers might need additional time to prepare their returns. The IRS allows for a six-month tax extension by submitting Form 4868 by the original due date. However, this extension is only applicable for filing and not for payment.

Following severe storms and disasters in March 2025, specific counties in Mississippi received tax relief. For residents in affected areas, including Calhoun and Carroll counties, the extended deadline for filing and tax payments is November 3, 2025.

Consequences of Not Filing

Failing to file your tax return on time can lead to serious penalties. The IRS imposes a penalty of 5% on the taxes due for each month that the return is late, up to a maximum of 25%. If your return is overdue by more than 60 days, the minimum penalty escalates to either $525 or 100% of the unpaid tax, whichever is lower.

Moreover, interest may accrue on these penalties. If a tax return is not filed, the IRS may initiate a substitute return on your behalf, potentially leading to an unpaid tax bill and further collection actions. Repeated failures can result in severe enforcement measures, including criminal prosecution.

Summary of 2026 MS Tax Deadlines

Filing Deadline: April 15, 2026, for federal and state taxes
Disaster Relief Deadline: November 3, 2025, for certain counties
Extension Request: Submit Form 4868 by the original deadline for a six-month extension

Staying proactive and organized is essential for navigating the tax season successfully in Mississippi. By being informed of key dates, taxpayers can avoid penalties and ensure timely filing of their taxes.