Treasury: Don’t Forget to File State Individual Income Tax Returns

Individual Income Tax Return Extension Deadline on October 15, 2026

Taxpayers who requested an extension to file their state individual income tax returns have less than a week to file a complete and accurate return, according to the Michigan Department of Treasury (Treasury).

State individual income tax returns due under an extension must be received by Treasury on or before Oct. 15, 2026. Returns can be sent through the U.S. Postal Service or e-Filed.

For the convenience of taxpayers, the extension deadline is the same as the Internal Revenue Service.

"Taxpayers should file a state individual income tax return if they haven't done so," said Deputy State Treasurer Kavita Kale, who oversees Treasury's Revenue Services programs. "Some individuals who haven't filed may be eligible for a refund through available tax credits. If you owe taxes and have hesitated to file and pay, please contact us so we can discuss your options."

Taxpayers who have yet to file their individual income tax return should consider:

• Filing a return to claim an outstanding refund. Taxpayers risk losing their state income tax refund if they don't file a return within four years from the due date of the original return. Go to www.michigan.gov/mifastfile to learn more about e-filing.
  
• Filing a return to minimize interest and penalties. File returns and pay now to limit interest charges and late payment penalties. An extension of time to file is not an extension of time to pay. Penalty and interest on the tax due is applicable from the original due date of the return until payment is received.
  
  
• Paying as much tax as possible. If taxpayers owe outstanding taxes and can't pay in full, they should pay as much as they can when they file their tax returns. Payment information can be found on Treasury's "Make a Payment" webpage. When mailing checks, carefully follow tax form instructions. Treasury will work with taxpayers who cannot pay the full amount of tax they owe.

As of Oct. 12, Treasury has processed more than 5.2 million individual income tax returns and issued $3.89 billion in refunds. Individual income tax returns are received and processed year-round, with most arriving between late January and April 15 during the filing season.

Questions?

Michigan taxpayers who have questions about or need help with their individual income tax returns or refunds can digitally connect with Treasury through Michigan Treasury eServices. Questions can also be directed to the Individual Income Tax Customer Contact Line at 517-636-4486.

To learn more about Michigan's individual income tax or to download forms, go to www.michigan.gov/incometax. For more information from Treasury, go to Michigan.gov/Treasury or follow @MiTreasury on X.