As per section 6 of the IGST Act following are the provisions related to the power to grant exemption for CGST:
(a) General Exemption: Central Government shall have power to grant general exemption wholly or partially on recommendation of the Council, if it is necessary in the public interest, by notification. Exemption may be either absolute or subject to some conditions as specified under the notification. Where such exemption is granted, such’ supply of goods and or service are not liable to tax.
(b) Special order: The Central or any State Government may on recommendation of Council, exempt from payment of tax, under circumstances of an exceptional nature to be stated in such order, any taxable goods and/or services, by special order in each case.
(c) The Central Government may:
(i) If necessary, for the purpose of clarifying the scope or applicability of any notification issued under sub-section (1) or order issued under sub-section (2) Of sec. 6,
(ii) Insert an explanation in such notification or order, as the case may be, by notification at any time within one year of issue of the notification under sub-section (1) or order under sub-section (2), and every such explanation shall have effect as if it had always been the part of the first such notification or order, as the case may be.
Effective Date: Every notification issued under sub-section (1) or sub-section (3) and every order issued under sub-section (2) of section 6 shall come into force from the date it is issued and published in the official Gazette or from the date specified therein. Such Notifications/order will also be made available at the official websites of Central Govt. or the State Govt.