Tax deduction at source on interest: prescribed withholding rates vary by payee class and security, subject to exemptions. Tax deduction at source is required on interest on Government securities at prescribed rates that vary by payee class - residents, non-residents and companies - and by security type, except where a valid exemption or abatement certificate is produced. Pre-existing operative certificates remain effective; certificates issued after the effective date determine rates for the specified person; specified bonds and savings instruments and certain exempt institutional holders and resident individuals meeting declaration and holding thresholds are not subject to deduction. Tax rounding and consultation requirements apply.