If you’re an employee who worked two different jobs in one year, you might have too much Social Security tax taken from your income. In 2010, workers pay Social Security tax of 6.2 percent on the first $106,800 of income. However, the 1.45 percent Medicare tax paid by both the employer and employee has no income limit. To get back any Social Security overage you paid on income greater than $106,800, you'll need to file some additional paperwork.
Identify the source of the overpayment. If you paid too much tax because you earned more than the limit at two different jobs, you can use your tax form to recoup the overage. However, if the error occurred because one employer goofed and withheld too much tax, you must get the overage back from your employer.
Total the Social Security tax your employers withheld. Do not include Medicare tax. In 2010, if the amount is more than $6,621.60 (6.2 percent times $106,800), you've overpaid. Subtract $6,621.60 from your payment. The difference equals the amount you'll get back from the government. Remember, even if you're married filing jointly, you'll have to calculate each person's Social Security tax individually. You don't combine incomes when it comes to this tax.
Write the amount of your Social Security overpayment in the "Payments" section on the back of your 1040 tax form. On the 2009 form, Social Security tax overpayments were entered on line 69.
Total all the federal tax payments you made during the year--via withholding, estimated payments and allowable credits--and include the excess Social Security tax withheld. The total is offset against your tax liability.
Remember, if you underpaid your regular income tax withholding, the excess Social Security helps offset the underpayment. There’s no guarantee you'll get the exact amount of overpaid Social Security tax back from the IRS. Just as Social Security tax owed by self-employed individuals adds to their total tax bill, any overpayment of Social Security tax reduces the tax bill, or adds to the refund.