Michigan Treasury Officials Grilled By Lawmakers Over Erroneous Tax Notices Sent to 27,000

LANSING, MI – Officials from the Michigan Department of Treasury faced intense questioning from state lawmakers this week regarding a system error that resulted in approximately 27,000 taxpayers receiving incorrect "Notice of Adjustment" letters in April. The error, tied to the rollout of a new tax processing platform, caused widespread confusion, payment demands, and significant refund delays, prompting a contentious House Oversight Committee hearing on Tuesday.

The faulty notices, dated between April 7 and April 28, were sent to individuals and businesses across the state. They incorrectly informed recipients that their tax refunds were being reduced or denied, that they owed additional taxes because prepayments had not been properly applied, or that there were errors related to estimated payments and credit carryforwards. This led to a surge of inquiries and complaints from taxpayers who had already paid their taxes or were awaiting expected refunds.

The issue stems from the implementation of a new tax system that officials described as “extremely precise.” During the hearing, Katina Litterini, director of tax administration for the Michigan Treasury, acknowledged that the new system's high level of precision in data validation had inadvertently caused the delays and triggered the erroneous notices. The department has since confirmed that taxpayer prepayments were, in fact, properly accounted for in its systems, and the notices were generated in error.

The fallout has been significant for those affected. Linda Aubochon of Ypsilanti told reporters she filed her taxes in February and was informed by her software that the state had accepted her filing and would be issuing a $2,035 refund. It took more than three months for the refund to arrive. Many others reported similar delays and an inability to get answers from the state.

Frustration was a key theme at the House Oversight Committee hearing, where legislators relayed constituents' difficulties in contacting the Treasury. Phone lines were frequently overwhelmed, with many taxpayers reporting constant busy signals. For those who managed to get through, wait times were often extensive. “Why would someone have to call Treasury that many times to try and get an answer from you?” asked Rep. Angela Rigas, R-Caledonia. She highlighted the particular burden this placed on older residents, noting, “The average age of these people is 65 and over. I think it’s completely unreasonable to require a taxpayer of that age to log on to your system when a phone call should be sufficient.”

In response to the grilling, Deputy State Treasurer Heather Kale acknowledged the department's misstep. “Yes, there was a mistake. We owned it. We problem-solved. We implemented the changes (and) that’s the best we can do,” Kale told the committee.

The Treasury has established a “Solutions Tracker” on its website to provide updates. The department stated it began mailing corrected letters to impacted taxpayers on May 5. According to a May 14 update, approximately 8,700 corrected notices had been issued, with the remaining taxpayers slated to receive revised letters and, if applicable, updated balance information through a “Reminder of Tax Due” notice. The department has advised that for most recipients of the incorrect letters, no action is required, and they should not send payments based on the erroneous notice.

This system glitch is not the only issue the Treasury has recently faced. The department’s tracker also notes a separate problem affecting Resident Tribal Members, who received letters incorrectly denying a sales tax credit due to another system issue. The department has also advised this group that no action is needed while a fix is implemented.

State-level system errors like this one in Michigan highlight a critical, often overlooked aspect of financial management for small and mid-sized businesses. While the Treasury's official guidance is that "no action is required," receiving an official notice demanding payment or altering an expected refund can cause immediate alarm and operational disruption. For a business owner, such a notice isn't just an inconvenience; it can create uncertainty around cash flow and trigger a time-consuming administrative scramble to verify payments and contact the state. In our experience, even when an error is widespread and acknowledged by the agency, the burden of proof often feels like it falls on the taxpayer. This is where professional guidance becomes invaluable. Proactive tax preparation and compliance services extend beyond simply filing documents; they involve monitoring for issues like this, interpreting agency notices, and managing the necessary follow-up to ensure a client’s account is corrected without them losing focus on running their business. Navigating these bureaucratic hurdles is a core part of what we do for clients at C&S Finance Group LLC at csfinancegroup.com.

Moving forward, affected Michigan taxpayers should continue to monitor their mail for the corrected notices from the Treasury. Meanwhile, state lawmakers are expected to maintain oversight of the new tax system's performance, particularly as the department works through the remaining erroneous cases. The incident has placed the long-term reliability of the state's new technology and its taxpayer service protocols under a microscope.