Software vendors received the below message from Michigan Treasury.
“MeF Processing Systems Updates
Michigan will be transitioning additional tax types over to a new vendor from 10/30/2026 to 11/12/2026. As a result, there will be impact to you and your customers.
Impacted tax types: Michigan Business Tax (MBT), Corporate Income Tax (CIT), Essential Services Assessment (ESA), and City Corporate, Individual (including city) and Fiduciary Income Tax.
MeF MBT, CIT, ESA and City Corp tax submissions will last be retrieved from the IRS MeF system on 10/30/2026 at 5:00 PM, with acknowledgments made available by 11:59 PM. Submissions sent after 10/30/2026 at 5:00 PM will not be retrieved until 11/12/2026 at 7:00 AM when the new systems come online. Submissions containing ACH direct debit payment requests with the Financial Transaction schema will not be withdrawn from taxpayer’s accounts until 11/13/2026. No additional penalty or interest will be charged on these payments.
MeF IIT (including city) and Fiduciary tax submissions will last be retrieved from the IRS MeF system on 11/4/2026 at 6:00 PM, with acknowledgments made available by 11:59 PM. Submissions sent after 11/4/2026 at 6:00 PM will not be retrieved until 11/12/2026 at 7:00 AM when the new systems come online. Submissions containing ACH direct debit payment requests with the Financial Transaction schema will not be withdrawn from taxpayer’s accounts until 11/13/2026. No additional penalty or interest will be charged on these payments.
We apologize for any inconvenience this may cause you and your customers and thank you for your continued patience during this transition period.“