Value of supply rules define transaction value and list inclusions and structured discount exclusions for GST valuation. The provision sets the value of supply as the transaction value where supplier and recipient are unrelated and price is sole consideration, and mandates inclusion of separately charged taxes and duties (other than specified GST enactments), amounts paid by recipient on supplier's behalf, incidental expenses, interest or penalties for delayed payment, and subsidies linked to price received by supplier. Discounts recorded on invoice or governed by pre-existing agreement with input tax credit reversal are excluded. Valuation where transaction value cannot be applied and notified classes of supplies shall follow prescribed methods.