Anyone earning income in the U.S. has to pay taxes on Social Security and Medicare. These are called FICA taxes for staff. FICA stands for the 'Federal Insurance Contributions Act' and has two parts. The first is Social Security and the second is Medicare. These taxes are actually referred to as OASDI (Old Age, Survivor and Disability Insurance). The Social Security portion of the tax is 12.4% on income up to $132,900 as of 2019 and the Medicare portion is 2.9% on all income.