This is what you need to do.
Determine your gross pay, either by multiplying your hourly rate of pay times the number of hours you work or by looking to your weekly salary.
Deduct your Social Security taxes by multiplying your gross pay by 6.2 percent (2009) and subtracting that number. If you receive $500 a week, you would thus need to deduct $31. Social Security taxes are capped at $106,800 annually, meaning once your gross annual pay rate reaches that figure, you no longer need to have Social Security deducted.
Take out Medicare taxes of 1.45% from your gross pay. Using the $500 example, you would deduct $7.25.
Determine your federal income tax withholding by first considering your marital status and your allowable deductions. If you are single, claiming a deduction of one, and are paid weekly, from that same $500, you would deduct $50, according to IRS Publication 15.
Deduct your state income tax. Income tax rates are determined by states and range from zero in Alaska, Florida, Nevada, New Hampshire, South Dakota, Texas, Tennessee, Washington and Wyoming to 11.8 percent in New Jersey and 11.7 percent in New York.
Deduct city taxes. While this is a less likely tax, if you work and live in New York City, you can expect to dole out more of your income to the Big Apple. Refer to the city government for exact rates.
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