Arizona A-4 & Withholding Calculator 2026

Arizona income tax withholding is a percentage of your gross taxable wages, which are generally the wages that will show in box 1 of your federal W-2 (your pay less pretax deductions such as health insurance premiums). On Form A-4 you choose one of seven percentages: 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0% or 3.5%. You can also have your employer withhold an extra flat amount from each paycheck.

Arizona's income tax itself is a flat 2.5% of your Arizona taxable income, after deductions and credits. A percentage of gross pay is only an approximation of that, so pick the percentage that gets you close and adjust the extra amount if you owe or are refunded a lot. For example, 2.0% of $65,000 is $1,300 a year, or $50 per biweekly paycheck.

All employees complete Form A-4, and new employees must do so within the first five days of employment. If you don't give the form to your employer, the department requires the employer to withhold 2.0% of your gross taxable wages. To change your percentage or your extra amount later, file a new A-4 with your employer.

Box 2 on the A-4 lets you elect a withholding percentage of zero if you expect no Arizona income tax liability for the year. Liability here is gross tax less credits such as the family tax credit, school tax credits and credits for taxes paid to other states. The election must be renewed every year: to keep it, give your employer a new A-4 by February 15 of the following year. If you don't, your employer withholds at the default 2.0% until you do. Zero withholding doesn't relieve you of tax you may owe when you file.