Input tax credit matching requires reconciliation with supplier returns; discrepancies add to recipient's output tax liability and attract interest. The provision requires matching of inward supply details with supplier outward supplies, import integrated tax, and duplication checks; matched credits are finally accepted and communicated. Discrepancies where claimed credit exceeds supplier-declared tax or where supplier returns are missing must be communicated to both parties; unresolved amounts are added to the recipient's output tax liability and attract interest from the date credit was availed. Duplication findings are added to output tax in the month of communication. If the supplier corrects returns within the prescribed time, the recipient may reduce its liability and receive an interest refund to the electronic cash ledger, limited to the interest paid by the supplier.