The Internal Revenue Service has announced a new round of penalty relief to eligible taxpayers who already filed their 2018 federal income tax returns but did not claim the previously offered waiver. This one-time penalty relief offering is estimated to benefit more than 400,000 eligible taxpayers. The IRS said in a statement that it will apply the estimated tax penalty waiver to tax accounts of all eligible taxpayers, so there is no need to contact the agency to apply for or request the waiver. Earlier this year, the agency had lowered the usual 90 percent penalty threshold to 80 percent to help taxpayers whose withholding and estimated tax payments fell short of their total 2018 tax liability. It had also removed the requirement that estimated tax payments be made in four equal installments, as long as they were all made by January 15, 2019. The automatic waiver applies to any individual taxpayer who paid at least 80 percent of their total tax liability through federal income tax withholding or quarterly estimated tax payments but did not claim the special waiver available to them when they filed their 2018 return earlier this year. IRS Commissioner Chuck Rettig said the the agency is taking this step to provide relief to any person who filed too early to take advantage of the waiver or was unaware of it when they filed. Copies of notices CP 21 granting this relief will be mailed to affected taxpayers over the next few months. Any eligible taxpayer who already paid the penalty will also receive a refund check about three weeks after their CP 21 notice. Those who have not requested penalty relief will also get the payment. The IRS urged taxpayers who have not yet filed their income tax returns to claim the waiver on their return. The Tax Cuts and Jobs Act introduced various changes in tax law, including the tax code overhaul, slashing individual income tax rates, eliminating personal exemptions and nearly doubling the standard deduction.