How to Determine the Amount of Federal Taxes Withheld
- 1). Subtract pretax expenses from your paycheck. Pretax expenses include 401k plan and 403b plan contributions as well as pretax health insurance payments. For example, if your monthly salary equals $3,000, but you have $400 in pretax costs, subtract $400 from $3,000 to get $2,600 of income subject to withholding.
- 2). Multiply the number of allowances you claim by the value of the allowance for your pay period. The IRS publishes the value in IRS Publication 15. For this example, in 2011, each monthly allowance equals $308.33, so if you claim one allowance, multiply 1 by $308.33 to get $308.33.
- 3). Subtract the value of your allowances from your income subject to withholding. In this example, subtract $308.33 from $2,600 to get $2,291.67.
- 4). Find the Percentage Method Table for your filing status and pay period in IRS Publication 15. Your filing status is either single or married. In this example, if you are married and paid monthly, find the monthly payroll period table for married persons.
- 5). Calculate your income tax withholding based on the table. In this example, in 2011, because your income is over $1,038 but under $3,204, subtract $1,038 from $2,291.67 to get $1,253.67. Multiply $1,253.67 by 0.15 to get $188.05. Add $70.90 to find that your income tax withholding equals $258.95.
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