Matching of input tax credit: unreconciled or duplicate claims are added to recipient output liability, with interest consequences. Matching of input tax credit requires reconciliation of a recipient's inward supplies with supplier outward returns, integrated import tax, and duplication checks; matching leads to final acceptance and communication. Discrepancies where claimed credit exceeds supplier-declared tax or where outward supplies are undeclared, and duplication of claims, are communicated to parties. Unresolved discrepancy amounts or duplicated credits are added to the recipient's output tax liability, subject to reduction if the supplier later files the return within prescribed time. Interest applies on added amounts from the date of availing credit, and refunded interest is limited to interest actually paid by the supplier and credited to the electronic cash ledger.