How is Social Security Financed?

Social Security is financed through a dedicated payroll tax. Employers and employees each pay 6.2 percent of wages up to the taxable maximum of $118,500 (in 2015), while the self-employed pay 12.4 percent.

In 2013, $726 billion (85 percent) of total Old-Age and Survivors Insurance and Disability Insurance income came from payroll taxes. The remainder was provided by interest earnings ($103 billion or 12 percent) and revenue from taxation of OASDI benefits ($21.1 billion or 3 percent), and $4.9 billion in reimbursements from the General Fund of the Treasury - most resulting from the 2012 payroll tax legislation.

The payroll tax rates are set by law, and for OASI and DI, apply to earnings up to a certain amount. This amount, called the earnings base, rises as average wages increase.

Tax rates for employees and employers each under current law
2000 and later 5.30 0.90 6.20
SOURCE: 2013 OASDI Trustees Report