Indiana Code Title 6. Taxation § 6-3.1-38-8

Sec. 8. (a) The amount of the credit provided by this chapter that a qualified taxpayer uses during a particular taxable year may not exceed the state tax liability of the qualified taxpayer.

(b) If the amount of a credit determined under this chapter for a particular qualified taxpayer and a particular taxable year exceeds the qualified taxpayer's state tax liability for that taxable year, then the qualified taxpayer may carry the excess over to the immediately succeeding taxable years.  The credit carryover may not be used for any taxable year that begins more than ten (10) years after the date on which the donation from which the credit results is made.  The amount of the credit carryover from a taxable year shall be reduced to the extent that the carryover is used by the qualified taxpayer to obtain a credit under this chapter for any subsequent taxable year.

(c) A qualified taxpayer is not entitled to a carryback or refund of any unused credit.