(a) As provided in this section, the Commissioner shall refund or credit any tax, penalty, or interest erroneously, illegally, or unconstitutionally collected or paid if application to the Commissioner for the refund shall be made within three years from the date the return was required to be filed. The application may be made by a customer who has actually paid the tax. The application may also be made by a person required to collect the tax, who has collected and paid over the tax to the Commissioner, provided that the application is made within three years of the payment to him or her by the customer, but no actual refund of monies shall be made to a person until he or she shall first establish to the satisfaction of the Commissioner, under such regulations as he or she may prescribe, that he or she has repaid to the customer the amount for which the application for refund is made. The Commissioner may, in lieu of any refund, allow credit on payments due from the applicant.(b) A person shall not be entitled to a revision, refund, or credit under this section of a tax, interest, or penalty that had been determined to be due pursuant to the provisions of section 9777 of this title where he or she has had a hearing or an opportunity for a hearing as provided in that section or has failed to avail himself or herself of the remedies therein provided. No refund or credit shall be made of a tax, interest, or penalty paid after a determination by the Commissioner made under section 9777 unless it be found that the determination was erroneous, illegal, or unconstitutional, or otherwise improper pursuant to law, in which event refund or credit shall be made of the tax, interest, or penalty found to have been overpaid.(c) If the Commissioner determines, on a petition for refund or otherwise, that a taxpayer has paid an amount of tax under this chapter that, as of the date of the determination, exceeds the amount of tax liability owing from the taxpayer to the State, with respect to the current and all preceding taxable periods, under any provision of this title, the Commissioner shall forthwith refund the excess amount to the taxpayer together with interest at the rate per annum established from time to time by the Commissioner pursuant to section 3108 of this title. That interest shall be computed from the latest of 45 days after the date the return was filed or from 45 days after the date the return was due, including any extensions of time thereto, with respect to which the excess payment was made or, if the taxpayer filed an amended return or otherwise requested a refund, 45 days after the date of such amended return or request was filed.(d) A person who sells oil subject to the tax imposed by 23 V.S.A. chapter 27 upon which the tax imposed by this chapter has been paid shall be entitled to a refund in the amount of such tax paid pursuant to this chapter. Such refunds shall be claimed in the manner set forth in this section.Added 1969, No. 144, § 1, eff. 6/1/1969; amended 1975, No. 154 (Adj. Sess.) § 11, eff. date, see note below; 1975, No. 190 (Adj. Sess.) § 1, eff. date, see note below; 1979, No. 105 (Adj. Sess.), § 48; 1981, No. 172 (Adj. Sess.), § 11c; 1983, No. 59, § 6, eff. 4/22/1983; 1997, No. 156 (Adj. Sess.), § 24, eff. 4/29/1998; 2013 , No. 73, § 47, eff. 6/5/2013.