How to Calculate the Federal Taxes Withheld
- 1). Consult IRS Publication 15 (see Resources) to find the value of each personal allowance per pay period. For example, as of 2010, if you were paid semiannually, you would find that each allowance reduces your income subject to federal income tax withholding by $1,825.
- 2). Multiply the value of your allowance per pay period by the number of personal allowances you claimed on your W-4 form. Continuing the example, if you claimed two allowances, you would multiply $1,825 by 2 to find the value of your allowances to be $3,650.
- 3). Subtract the value of your personal allowances from your periodic pay. In this example, if you were paid $45,000 semiannually, you would subtract $3,650 from $45,000 to get $41,350.
- 4). Use the appropriate tax withholding table found in IRS Publication 15 to calculate your income tax withholding based on your pay period and filing status. Finishing the example, if you were married, you would use the semiannual payroll period chart for married people to find that your income tax withholding would be $5,250.
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