Monthly returns and payment of excise; tax rate

Section 4. At the time of filing a return required by subsection (a) of section sixteen of chapter sixty-two C, every distributor and unclassified exporter shall pay to the commissioner an excise at the tax per gallon determined by the commissioner upon each gallon of fuel sold by him in the commonwealth during the calendar month covered by the return.

At the time of filing a return required by paragraph (a) of section sixteen of chapter sixty-two C, every unclassified importer shall pay to the commissioner an excise at the tax per gallon determined by the commissioner upon each gallon of fuel imported or caused to be imported during the calendar month covered by the return.

Notwithstanding the foregoing, the tax per gallon payable upon each gallon of fuel sold, imported or caused to be imported as aviation fuel shall be separately determined by the commissioner utilizing the same procedures as those used for other fuel and such tax per gallon as so determined shall apply to each gallon of fuel sold, imported or caused to be imported as aviation fuel by a licensee in the commonwealth during the calendar month covered by the return.