An extension to file is not an extension to pay tax.
Michigan does not treat a federal extension as automatically extending the state deadline. A taxpayer must submit an estimated payment of remaining tax due, along with either a copy of the federal extension (Form 4868) or Michigan's own Form 4, by the original due date.
| Item | Detail |
|---|---|
| Automatic | No - filing a federal extension alone does not extend the Michigan deadline |
| What to submit | An estimated payment of remaining tax due, plus a copy of federal Form 4868/7004 or Michigan Form 4 |
| Due date | By the original return due date |
| Extended due date | Michigan Treasury extends the due date to match the new federal due date |
| Payment requirement | This is a filing extension only - underpayment results in interest (1% above prime rate) plus a penalty of 10% or more |
| Refund exception | No extension is needed if a refund is expected; refunds can be claimed up to 4 years from the original due date |
| Authority | Mich. Comp. Laws §206.311 |