Input tax credit matching leads to additions to recipient output tax liability unless supplier declarations rectify discrepancies. Claims for input tax credit are matched against suppliers' outward returns, import tax and duplicate claims; matching claims are accepted. Discrepancies where recipient claims exceed supplier declaration are communicated to both parties, and unrectified amounts are added to the recipient's output tax liability. Duplicative credits are added when communicated. Recipients may reverse additions if suppliers timely declare the invoices; interest applies on added amounts from the date of availing credit and may be refunded to the recipient's electronic cash ledger, limited to interest paid by the supplier.