law: The Central Goods and Services Tax Act, 2017
  41. Claim of input tax credit and provisional acceptance thereof.-
  (1) Every registered person shall, subject to such conditions and restrictions as may be prescribed, be entitled to take the credit of eligible input tax, as self-assessed, in his return and such amount shall be credited on a provisional basis to his electronic credit ledger.
  (2) The credit referred to in sub-section (1) shall be utilised only for payment of self-assessed output tax as per the return referred to in the said sub-section.