All MBT taxpayers must file a final MBT return for the tax year ending on December 31, 2011, including a fiscal year taxpayer that will be subject to the CIT. 

A taxpayer that is subject to the MBT and the CIT for fractional parts of the same fiscal tax year must use the same method to compute the MBT as used to compute the CIT for the other portion of the tax year.  MCL 208.1503(2) and MCL 206.683.  More specifically, MCL 206.683(1) directs that a taxpayer subject to the CIT may elect to compute the tax for the portion of the tax year to which the CIT applies by 1 of the following methods:

1. Annual - The tax may be computed as if the CIT was effective on the first day of the taxpayer's annual accounting period and the amount computed shall be multiplied by a fraction, the numerator of which is the number of months in the taxpayer's first tax year and the denominator of which is the number of months in the taxpayer's annual accounting period.
   
   
2. Actual - The tax may be computed by determining the corporate income tax base in the first tax year in accordance with an accounting method satisfactory to the department that reflects the actual corporate income tax base attributable to the period. The method of accounting used in prior fiscal years will be assumed to reflect the actual tax base attributable to the period.

MCL 206.683(2) further states that the method chosen by the taxpayer to compute the CIT shall be the same method used by that same taxpayer when computing the MBT for the other portion of that same tax year.