Section 8(2) in Goods and Services Tax (Compensation to States) Act, 2017
(2)The cess shall be levied on such supplies of goods and services as are specified in column (2) of the Schedule, on the basis of value, quantity or on such basis at such rate not exceeding the rate set forth in the corresponding entry in column (4) of the Schedule, as the Central Government may, on the recommendations of the Council, by notification in the Official Gazette, specify:Provided that where the cess is chargeable on any supply of goods or services or both with reference to their value, for each such supply the value shall be determined under section 15 of the Central Goods and Services Tax Act for all intra-State and inter-State supplies of goods or services or both:Provided further that the cess on goods imported into India shall be levied and collected in accordance with the provisions of section 3 of the Customs Tariff Act, 1975, at the point when duties of customs are levied on the said goods under section 12 of the Customs Act, 1962, on a value determined under the Customs Tariff Act, 1975.
