PIT-UND: Underpayment of Estimated Taxes (2024)
Delaware · Delaware Division of Revenue · Used for tax years 2024
Delaware Form PIT-UND calculates underpayments of estimated taxes and any related penalty for 2024. It includes a short method and an annualized installment method, using your Delaware tax liability, withholding, payments, and applicable credits.
When it's due
For tax year 2024, Part 5 prints these payment due dates:
- May 1, 2024
- June 15, 2024
- September 15, 2024
- January 15, 2025
These are the payment dates printed in the penalty calculation section, not a stated deadline for filing PIT-UND.
What you'll need
Have these returns and records available for the amounts the form asks you to enter:
- Your 2024 Delaware PIT-RES or PIT-NON return, for tax liability and other applicable amounts.
- Your 2023 Delaware PIT-RES or PIT-NON return, for the prior-year tax liability calculation.
- Records of Delaware withholding, estimated tax payments, S corporation payments, and refundable business credits. Part 4 also asks for capital gain tax payments.
- Payment dates and amounts, for the penalty calculation.
If you use the annualized installment method, you will also need Delaware adjusted gross income and any itemized deductions for the periods shown, plus applicable deductions and credits. The form directs you to use the tax table or tax schedule to calculate tax.
Common mistakes
- Do not continue past Part 1, Line E if Line C minus Line D is $800 or less. The form says to stop because you do not owe the penalty.
- In the short method, stop if total underpayment on Line I is zero or less.
- For annualized itemized deductions, enter zero on Line 5 if you did not itemize. Enter zero on Line 8 for the standard deduction if you itemized.
- Check the box in Part 3 if you used a non-resident return.
- Follow the previous-column carryover directions carefully in Parts 3 and 4.
Questions people ask
How is the required annual amount calculated?
Part 1 compares 90% of your 2024 Delaware tax liability with 100% or 110% of your 2023 Delaware tax liability. Enter the smaller amount on Line C. The form refers to instructions for choosing 100% or 110%, but those instructions are not included in the supplied text.
When does the form say I do not owe a penalty?
Part 1 says to subtract Delaware withholding on Line D from the required annual amount on Line C. If the result is $800 or less, stop. You do not owe the penalty.
How does the short method calculate the penalty?
Multiply total underpayment on Line I by 12% to get Line J. If Line I was paid before April 30, 2025, calculate Line K using the number of days paid before that date, multiplied by .05% (.0005), multiplied by Line I. If paid on or after April 30, 2025, enter zero on Line K. Subtract Line K from Line J to get the estimated penalty.
Does the form include an annualized installment method?
Yes. Part 3 includes calculations for the periods January 1 through March 31, May 31, August 31, and December 31, 2024. It uses income and deductions for each period to calculate annualized installment amounts.