221: of Estimated Tax by Individuals Form (2025)
Arizona · Arizona DOR · Used for tax years 2025
Arizona Form 221 calculates an individual's underpayment of estimated tax and any resulting penalty for 2025. It includes an annualized income installment worksheet and is included with Form 140, 140PY, or 140NR.
Who files this form
Arizona Form 221 calculates underpayment of estimated tax and the related penalty for individuals filing Form 140, Form 140PY, or Form 140NR.
If your 2025 tax after credits, minus Arizona tax withheld, is less than $1,000 on line 6, stop. The form says you do not owe the penalty and should not file Form 221.
Line 1 lets you claim an exception from the estimated payment penalty if you qualified for federal relief under IRC § 6654. It directs you to instructions, which are not included in the supplied text.
When it's due
For tax year 2025, Form 221 lists these estimated payment due dates:
- April 15, 2025
- June 16, 2025
- September 15, 2025
- January 15, 2026
The form says to include it with your return, but does not state a separate filing deadline for Form 221.
What you'll need
Have the following information available to complete the form:
- Your name and Social Security number, plus your spouse’s name if filing a joint return.
- Your 2025 Arizona Form 140, Form 140PY, or Form 140NR tax and tax credit amounts.
- Your Arizona tax withheld during 2025.
- Your estimated tax payment amounts and payment dates.
- Your immediately preceding year’s tax liability after tax credits.
If you use the annualized income installment method, you also need the income, deduction, exemption, and tax credit amounts requested for each period on the page 2 worksheet.
How to file
Include Form 221 with your Arizona return. The form identifies Forms 140, 140PY, and 140NR.
If you annualize income, complete the worksheet on page 2 and transfer each column’s line 23 amount to the matching column on page 1, line 11.
The supplied form does not provide a mailing address or e-filing directions.
Common mistakes
- Do not include estimated tax payments or extension payments on line 5. That line is only for Arizona tax withheld during 2025.
- Do not file Form 221 if line 6 is less than $1,000. The form says to stop because you do not owe the penalty.
- Complete lines 13 through 15 of one column before starting line 13 of the next column.
- Check the box on line 11 if you use another installment method. If you annualize, complete the page 2 worksheet.
- On the annualized income worksheet, complete lines 1 through 23 of one column before moving to the next.
Questions people ask
How is the required annual payment calculated?
Line 9 uses the smaller of 90% of your 2025 tax after credits or your immediately preceding year’s tax liability after tax credits.
How many installments does the form normally use?
Line 11 says to divide the required annual payment by the number of payments required for the year, usually four.
Can I annualize my income?
The form provides an Annualized Income Installment Worksheet on page 2. If you annualize, enter its line 23 amounts in the corresponding columns of page 1, line 11.
Does the form provide every penalty rate needed?
No. It lists 7% for the first three rate periods, but marks the rate for January 1 through April 15, 2026, as a percentage to be determined.