Enter the amount of your pretax contribution to your retirement plan.
Enter the applicable tax rate. This amount should represent the total tax rate that would apply if you had not made the pretax contribution, taking into consideration all of your taxable income. In general, consider marginal federal, state, and local income tax rates, as appropriate. State and local tax rates are generally relevant only if an income tax is imposed on your wages at the state or local level and taxable wages are reduced by salary reduction contributions.