How to Determine the Amount of Social Security Tax Withheld

There are some differences in Social Security tax calculations.

For 2009, the Social Security tax rate was 15.3 percent. In 2012, that tax rate is 13.3 percent. If you are an employee, you pay approximately 40 percent of the Social Security tax, and your employer pays approximately 60 percent. If you are self-employed or an independent contractor, you are responsible for calculating and paying the entire amount of the Social Security tax, which is composed of the employee and employer SSI taxes, plus the Medicare tax.. Social Security taxes pay for retirement benefits paid out the elderly, and for survivor benefits in case of an untimely death.

For Employees

Step 1

Collect your W-2 forms from all of your jobs. If you only have one employer, there will only be one form to check.

Step 2

Look to Box 4 of the W-2 form to find the amount of Social Security tax withheld.

Step 3

Add all of the numbers in Box 4 together to determine the amount of Social Security tax withheld during the year. For 2012, Social Security taxes are limited to the first $110,100 you earn. If your only income is from employers, you should not pay more than $4,624.20 (4.2 percent of $110,100) in Social Security taxes. If your total exceeds this amount, you may be entitled to a refund of some of the money that was withheld. If you find that too much was withheld, you can file a Form 843 to request a refund of the excess.

For the Self-Employed

Step 1

Total all of your self-employment income for the year. For example, you may have had $34,000 in self-employment income.

Step 2

Multiply your income total by 92.35 percent. For example, if you had $34,000 in self-employment earnings, 92.35 percent would total $31,399. If this amount is less than $400, you do not have to pay Social Security taxes. If it is over $400, you must pay as detailed below.

Step 3

Multiply the amount in Step 2 by 13.3 percent. For example, if you had $31,399 in qualifying earnings as figured in Step 2, you would owe $4,176.07 in Social Security taxes. Social Security taxes are part of self-employment taxes; the other part is the 2.9 percent Medicare tax. When you file your return, you can deduct half of your self-employment taxes from your taxable income.


When calculating your self-employment social security taxes, do not forget to calculate your medicare taxes as well, as they are both included to Social Security payment calculations, and you are responsible for both when you are self-employed.

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