Interest for defaults in payment of advance tax triggers monthly simple interest where advance payments fall short of assessed tax.
The provision charges simple interest where a taxpayer fails to pay advance tax or pays less than the safe harbour proportion of assessed tax, starting from 1 April following the tax year until determination of total income or completion of regular assessment. Interest is computed on assessed tax or the shortfall, with the assessed tax base reduced by specified items such as tax deducted/collected at source, reliefs and eligible tax credits; reassessment or recomputation increases or reduces interest accordingly and payments already made reduce liability.