Unitary Business Groups 6. How is the CIT tax base calculated for a unitary business group?

Under MCL 206.623(3), the tax base of a unitary business group is the sum of the business income of each group member minus any income and related deductions arising from inter-group transactions. Certain additions and subtractions to business income are outlined in MCL 206.623(2) and must be made before allocation or apportionment to arrive at the unitary group's income tax base. After the tax base is allocated or apportioned, the tax base is adjusted by available business loss as set forth in MCL 206.623(4). The tax base of a financial institution unitary business group is calculated under MCL 206.655 and 206.657.