VAT is calculated by deducting tax credit from tax collected during the payment period.
Example: (Rate of tax assumed at 10%). Purchase Price 100. Tax paid on purchase 10(input tax). Sale Price 150. Tax payable on sale price 15(output tax). Input tax credit 10. VAT payable 5. Total tax collection by govt. -------- On the sale price of100 paid on the purchase by the dealer 10. Net VAT paid by the dealer on value addition after resale 5. Total tax at 10% on the last sale price of150 15.