The Michigan Department of Treasury has been made aware that some "Reminder of Tax Due" letters sent to taxpayers contain an incorrect toll-free (1-800) TTY number, which may connect callers to a potential scam. Taxpayers with questions regarding unpaid individual income taxes are asked to contact the Treasury directly at 517-636-4486. We apologize for any confusion or concern this may have caused.
How are penalty/interest charges calculated for failure to file or underpayment of estimated payments?
Penalty is 25% for failure to file estimated payments or 10% of underpaid tax per quarter.
For exceptions see MCL 205.23(3)
Interest is 1% above the prime rate.
For more information view Penalty and Interest for Underpayment of Estimates (MI-2210)