Internal Revenue Code Section 280C requires a taxpayer who elects to claim certain credits that are based on an expense to reduce the federal deduction for the expense by the dollar amount of the credit claimed. Under R.S. 47:287.73(C)(4) Louisiana allows the deduction of any expenses disallowed under IRC Section 280C in calculating Louisiana taxable income for corporations. Therefore the amount of the expense disallowed under IRC Section 280C can be deducted in calculating taxable income for Louisiana.

For returns filed on or after July 1, 2015, but before June 30, 2018, regardless of the tax year to which it relates, and returns for tax periods beginning during the calendar years of 2015, 2016, and 2017, 72 percent of expenses which would otherwise be deductible under federal law, can be deducted in calculating taxable income for Louisiana.

A corporation would show this modification to income on Form CIFT-620, on Schedule D and Schedule F as a subtraction. (Question & answer revised June 15, 2021).