Penalty and interest on delinquent tax

1. A penalty is imposed on delinquent tax in the amount of five percent of the delinquent tax or five dollars, whichever is greater. This penalty does not apply to delinquent tax reported on an amended return if: a. Ninety percent of the total combined tax liability, reported on the original return and amended returns, was paid with the taxpayer's original return; and b. The amended return is filed and all delinquent tax is paid within sixty days of the due date of the original return. 2. Interest is imposed on delinquent tax at a rate of one percent per month for each calendar month or any part of a month in which the tax remains unpaid, except that interest is not imposed in the month the delinquent tax became due. The commissioner will consider a taxpayer's oral or written request for a waiver of penalty and interest and may grant a waiver in accordance with sections 81-01.1-01-09 and 81-01.1-01-10. Penalty and interest collected by the commissioner on delinquent tax must be apportioned in the same manner as the delinquent tax. The amount of penalty and interest due will be determined in the following manner: a. The penalty and interest rates must be applied to delinquent tax for each production period. Multiple tax underpayments for different production periods will not be combined to calculate penalty and interest. Tax overpayments and tax underpayments for different production periods will not be offset to calculate penalty and interest. b. The penalty and interest rates must be applied to the delinquent tax computed on an original or amended return. Tax overpayments and tax underpayments for individual well or unit entries on a single return will be offset and the penalty and interest computed on the net delinquent tax. Tax overpayments and tax underpayments reported on separate returns for the same production period will not be offset.