Tax Penalty IRS or State Late Filing or Late Tax Payment Penalties ∗ IRS Tax Penalty Calculator. Late Filing and Payment Calculator. ∗ IRS Tax Return Penalty Calculator. Late Filing and Late Payment Interest and Penalty Calculator. Estimate Penalties by Tax Year; Late Filing or Payment Penalties; What Happens If You File Late? Penalties Due to Late Filing or Late Payment of Taxes. File Something on Time Even If You Can''t Pay Anything to Reduce Tax Penalties. IRS Interest Rates by Tax Year and Quarter for Under- Over Pay Overview on How the IRS Calculates Late Tax Filing Penalties and Interest. Late Filing Penalties Are Higher Than Late Payment Penalties TurboTax® is a registered trademark of Intuit, Inc. H&R Block® is a registered trademark of HRB Innovations, Inc.