For a calendar year taxpayer, MBT quarterly returns are due the 15th day of April, July, October and January. For fiscal year filers, quarterly returns are due the 15th day of the first month after each quarter. MBT payments may be made with either of the following returns:

• Form 4548, Michigan Business Tax Quarterly Return, or
• Form 160, Combined Return for Michigan Taxes.

If filing monthly using Form 160, Combined Return for Michigan Taxes, and not making remittances by electronic funds transfer, monthly payments may be filed on the 20th day of the month.  For example, a calendar year taxpayer may file monthly MBT estimates using Form 160 on February 20th, March 20th and on April 20th rather than April 15 for the first quarter.  However, for taxpayers required to make remittances by electronic funds transfer or otherwise not using Form 160, MBT estimates remain due on the 15th day of the month following the final month of the quarter.  Regardless of the method chosen, the estimated MBT for the quarter must also reasonably approximate the liability for the quarter.