What is an extension?

An extension is a request for more time to file your Michigan tax return. It is only an extension of time to file, not an extension of time to pay.

To request more time to file your Michigan tax return, send a payment of your remaining estimated tax to Treasury with a copy of your federal extension (U.S. Form 4868) on or before the original due date of your return. Treasury will extend the due date to your new federal due date. If you do not have a federal extension, file an Application for Extension of Time to File Michigan Tax Returns (Form 4) with your payment. Treasury will not notify you of approval. An extension is not necessary when you expect to claim a refund. Late filing penalty may not apply as refunds can be claimed up to 4 years from the original due date without an extension.

If you do not pay enough with your extension request, you must pay interest on the unpaid amount. Compute interest from the original due date of the return. Interest is 1% above the prime rate and is adjusted on July 1 and January 1.

You may be charged a penalty of 10% or more if the balance due is not paid with your extension request.

When you file your MI-1040, include on line 31 the amount of tax you paid with your extension request. Include a copy of your federal or state extension with your return.