“Penalty for underpaying your estimated tax
We may charge you a penalty on the amount of estimated income tax that you didn’t pay or paid late during the year (either through estimated tax payments, withholding tax, or a combination of the two). The penalty you will have to pay will equal the federal short-term interest rate plus five and one half percentage points (adjusted quarterly), but not less than 7.5%.
The underpayment penalty applies if your 2012 withholding and estimated income tax payments do not equal:
- 90% of the income tax shown on your 2012 return
- 100% of the income tax shown on your 2011 tax return if your NYS AGI is $150,000 or less
- 100% of the income tax shown on your 2011 return if married filing separately for 2012 and your NYS AGI is $75,000 or less
- 110% of the income tax shown on your 2011 return if your NYS AGI is more than $150,000, or
- 110% of the income tax shown on your 2011 return if married filing separately for 2012 and your NYS AGI is more than $75,000
Note: Special rules apply to farmers and fishermen. See Form IT-2105.9-I. Instructions for Form IT-2105.9, Underpayment of Estimated Tax by Individuals and Fiduciaries.
If you determine that you underpaid or paid your estimated tax late, you must calculate the amount of your penalty using Form IT-2105.9, Underpayment of Estimated Income Tax by Individuals and Fiduciaries. Attach Form IT-2105.9 to your return.”
http://www.tax.ny.gov/pit/estimated_tax/estimated_tax_payment_due_dates.htm
http://www.tax.ny.gov/bus/ct/ct222.htm