Understanding GST Refund under Rule 89(4) is crucial for every exporter and eCommerce entrepreneur in India. This rule explains how to calculate refund of unutilised Input Tax Credit (ITC) on zero-rated supplies like exports or supplies to SEZ made without payment of IGST under LUT or Bond. The formula for refund under Rule 89(4) is: Refund = (Turnover of zero-rated supply of goods Turnover of zero-rated supply of services) × Net ITC ÷ Adjusted Total Turnover. Here, Turnover of zero-rated goods