IT-2105.9: Underpayment of Estimated Income Tax By Individuals and Fiduciaries for tax year 2024 (2024)
New York · NY DTF · Used for tax years 2024
New York Form IT-2105.9 is used by individuals and fiduciaries to calculate underpayment of estimated tax and any resulting penalty for 2024. It compares tax owed with withholding and estimated tax payments and provides short and regular methods for computing the penalty.
Who files this form
Form IT-2105.9 is for individuals and fiduciaries calculating an estimated tax underpayment penalty for New York State, New York City, Yonkers, and MCTMT.
All filers using this form must complete Part 1. If line 15, current-year tax minus income taxes withheld, is less than $300, the form says not to complete the rest of the form. It also directs you to the instructions.
When it's due
For tax year 2024, the form prints these estimated tax payment due dates:
- April 15, 2024
- June 15, 2024
- September 15, 2024
- January 15, 2025
The 2024 penalty calculation also uses April 15, 2025. Under the short method, line 23 depends on whether the underpayment was paid before that date or on or after it.
What you'll need
Have these records and figures available:
- Your name and Social Security number or employer identification number, as shown on your return.
- Your 2024 New York return, Form IT-201, IT-203, or IT-205, for tax, withholding, and applicable credit amounts.
- Your 2023 tax information for line 16.
- Your total STAR credit amount, if applicable.
- Records of estimated tax payments, including amounts and payment dates.
The form refers to Form IT-2105.9-I for help, including cautions about the tax amounts to enter on lines 1 and 16.
How to file
Submit Form IT-2105.9 with your New York State return.
Enter the penalty from line 24 or line 39 on the applicable return:
- Form IT-201, line 81
- Form IT-203, line 71
- Form IT-205, line 42
The supplied form does not provide a mailing address or e-filing directions.
Common mistakes
- Overlooking the cautions on tax amounts: Lines 1 and 16 specifically say to see the instructions before entering your 2024 and 2023 tax amounts.
- Continuing when line 15 is less than $300: The form says not to complete the rest of the form and refers you to the instructions.
- Leaving out the form when submitting your return: The form reminds you to submit it with your New York State return.
Questions people ask
When can I use the short method?
Part 2 says to use the short method if you paid withholding tax and/or four equal estimated tax installments on the due dates, or if you made no estimated tax payments. Otherwise, complete Part 3, the regular method.
What if line 21 is zero or less?
Under the short method, if line 21 is zero or less, you do not owe the penalty.
Does paying before April 15, 2025, affect the short-method calculation?
Yes. For tax year 2024, if the amount on line 21 was paid before April 15, 2025, line 23 is that amount multiplied by the number of days paid before April 15, 2025, multiplied by .00026. If it was paid on or after that date, enter zero on line 23. Subtract line 23 from line 22 to calculate the penalty.
How do I work through the regular-method columns?
In Part 3, Schedule A, complete lines 27 through 29 one column at a time, starting with column A.