Refund of tax and unutilised input tax credit governed by time limits, documentary proof, provisional payments and withholding rules. Claims for refund of tax, interest or other amounts require prescribed forms, supporting evidence and are subject to time limits: generally within two years from the relevant date, with special shorter periods for notified international entities. Registered persons may claim refund of unutilised input tax credit in defined cases such as zero-rated supplies and where input tax rates exceed output rates, subject to exclusions. Proper officers must decide within sixty days, may grant provisional refunds for zero-rated supplies, and may withhold or adjust refunds for defaults, unpaid liabilities or suspected fraud, with limited interest where withholding is reversed.