<P> The combined tax rate of these two federal programs is 15.30% (7.65% paid by the employee and 7.65% paid by the employer). In 2011 - 2012 it temporarily dropped to 13.30% (5.65% paid by the employee and 7.65% paid by the employer). </P> <P> For self - employed workers (who technically are not employees and are deemed not to be earning "wages" for federal tax purposes), the self - employment tax, imposed by the Self - Employment Contributions Act of 1954, codified as Chapter 2 of Subtitle A of the Internal Revenue Code, 26 U.S.C. § § 1401--1403, is 15.3% of "net earnings from self - employment ." In essence, a self - employed individual pays both the employee and employer share of the tax, although half of the self - employment tax (the "employer share") is deductible when calculating the individual's federal income tax . </P> <P> If an employee has overpaid payroll taxes by having more than one job or switching jobs during the year, the excess taxes will be refunded when the employee files his federal income tax return . Any excess taxes paid by employers, however, are not refundable to the employers . </P> <P> Workers are not required to pay Social Security taxes on wages from certain types of work: </P>

What of us gov revenues is social security contributions