Citi Benefits Handbook
Social Security Taxes
Each year you pay Social Security taxes on a certain amount of your earnings, called the taxable wage base. Since the before-tax contributions are not considered part of your pay for Social Security tax purposes, your Social Security taxes will also be reduced if your pay falls below the taxable wage base after these before-tax dollars are subtracted from your total earnings. In this case, your future Social Security benefit may be smaller than if after-tax dollars were used for providing those benefits.