August 6, 2019 The new Tax Withholding Estimator makes it easier for retirees to pay the correct amount of tax. This tool helps you tailor the amount of tax withheld from your income to target a tax due amount close to zero or a refund amount. New features for pension income provide more accurate estimates of withholding. It even automatically calculates any taxable Social Security benefits. Use the Tax Withholding Estimator’s recommendations to complete a new Form W-4P, if needed, and give it to your payer.