Deduction at source: prepaid taxes are credited against liability and failure to remit renders the person an assessee in default. Tax on income is payable in the previous year by deduction, collection or advance payment; such pre-paid taxes are creditable against total tax. Employer payment for non-monetary perquisites counts as a mode of collection. If withholding is not provided or tax is not deducted, the assessee must pay directly by advance tax or otherwise. Specific timing applies to direct payment on certain employee share benefits from eligible start-ups. A person required to deduct or collect tax who fails to do so, and where the assessee also fails to pay, is deemed an assessee in default for the unpaid tax.