Section 54A:9-5 - Interest on underpayment(a) General. If any amount of income tax is not paid on or before the last date prescribed in this act for payment, interest on such amount at the rate as is required under the State Tax Uniform Procedure Law, R.S. 54:48-1 et seq. If the time for filing of a return of tax withheld by an employer is extended, the employer shall pay interest for the period for which the extension is granted and may not charge such interest to the employee.(b) Exception as to estimated tax. This section shall not apply to any failure to pay estimated tax under section 54A:8-5.(c) (Deleted by amendment, P.L. 1987, c.76.)(d) (Deleted by amendment, P.L. 1987, c.76.)(e) Suspension of interest on deficiencies. If a waiver of restrictions on assessment of a deficiency has been filed by the taxpayer, and if notice and demand by the director for payment of such deficiency is not made within 30 days after the filing of such waiver, interest shall not be imposed on such deficiency for the period beginning immediately after such 30th day and ending with the date of notice and demand.(f) Interest treated as tax. Interest under this section shall be paid upon notice and demand and shall be assessed, collected and paid in the same manner as income tax. Any reference in this act to the tax imposed by this act shall be deemed also to refer to interest imposed by this section on such tax.(g) (Deleted by amendment, P.L. 1992, c.175.)(h) Payment prior to notice of deficiency. If, prior to the mailing to the taxpayer of a notice of deficiency under subsection (b) of section 54A:9-2, the director mails to the taxpayer a notice of proposed increase of tax and within 30 days after the date of the notice of proposed increase the taxpayer pays all amounts shown on the notice to be due to the director, no interest under this section on the amount so paid shall be imposed for the period after the date of such notice of proposed increase.(i) Payment within 10 days after notice and demand. If notice and demand is made for payment of any amount under subsection (b) of section 54A:9-12, and if such amount is paid within 10 days after the date of such notice and demand, interest under this section on the amount so paid shall not be imposed for the period after the date of such notice and demand.(j) Limitation on assessment and collection. Interest prescribed under this section may be assessed and collected at any time during the period within which the tax or other amount to which such interest relates may be assessed and collected, respectively.(k) Interest on erroneous refund. Any portion of tax or other amount which has been erroneously refunded, and which is recoverable by the director, shall bear interest as is required under the State Tax Uniform Procedure Law, R.S. 54:48-1 et seq.(l) Satisfaction by credits. If any portion of a tax is satisfied by credit of an overpayment, then no interest shall be imposed under this section on the portion of the tax so satisfied for any period during which, if the credit had not been made, interest would have been allowable with respect to such overpayment.Amended 1987, c.76, s.58; 1992, c.175, s.43.