An employer-sponsored retirement savings account could be one of your best tools for creating a secure retirement. Pre-tax contributions are tax-deferred, you only pay taxes on contributions and earnings when the money is withdrawn. After-tax contributions are after-tax and are tax free when the money is withdrawn. Use this calculator to see how increasing your contributions to a 457 plan can affect your paycheck as well as your retirement savings. This calculator uses the latest withholding schedules, rules and rates (IRS Publication 15).