Answer:
a) Is Santhosh required to increase his withholding or make estimated tax payments this year to avoid the underpayment penalty?
- No he is not required to make any payments or increase his withholdings because this year's withholdings already represent a 133% increase with respect to last year's tax liability. If the withholdings for the current are over 100% last year's tax liability, then the taxpayer doesn't need to make any further adjustments in order to avoid underpayment penalties.
b) By how much, if any, must Santhosh increase his withholding and/or estimated tax payments for the year to avoid underpayment penalties?