An employer-sponsored retirement savings account could be one of your best tools for creating a secure retirement. It provides two important advantages. First, all contributions and earnings are tax-deferred. You only pay taxes on contributions and earnings when the money is withdrawn. Second, many employers provide matching contributions to your account, which can range from 0% to 100% of your contributions. Use this calculator to see how increasing your contributions to a 401(k), 403(b) or 457 plan can affect your paycheck as well as your retirement savings. Withholding schedules, rules and rates are from "IRS Publication 15" and "IRS Publication 15T". This calculator uses the redesigned W-4 created to comply with the elimination of exemptions in the Tax Cuts and Jobs Act (TCJA).