Input tax credit requires invoice, receipt, tax payment and return filing; credit reversed if recipient fails to pay supplier. Entitlement to input tax credit is limited to registered persons using supplies in the course of business and contingent on possession of a tax invoice or prescribed document, actual receipt of goods or services (including deemed receipt), payment of the tax charged to Government in cash or by allowable credit utilisation, and filing the statutory return. Credit on goods received in instalments accrues only on the final instalment. Credit is disallowed if depreciation was claimed on the tax component of capital goods, and claims are time-barred after the due return for the September month following the financial year or filing the annual return; failure to pay the supplier within the prescribed period triggers reversal with interest, reversible upon payment.