IRS Penalty Calculator

Calculate failure-to-file and failure-to-pay penalties with interest.
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Use the IRS Penalty Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.

How It Works

Our IRS Penalty Calculator helps you estimate the failure-to-file and failure-to-pay penalties, including interest, for tax year 2026. Understanding these penalties is crucial to avoid unexpected financial burdens and ensure timely tax compliance. This tool provides a clear breakdown of potential costs, helping you plan accordingly.

The failure-to-file penalty is 5% of the unpaid taxes for each month or part of a month the return is late, capped at 25%, with a minimum penalty for returns over 60 days late of $485 for 2026. The failure-to-pay penalty is 0.5% of the unpaid taxes for each month or part of a month the taxes remain unpaid, capped at 25%. Interest on underpayments for Q1 2026 is 8% per annum, compounded daily, added to both penalties and the original tax due.

Remember, filing an extension only grants more time to file, not to pay; payments are still due by the original deadline to avoid failure-to-pay penalties. Always pay as much as you can by the original deadline, even if you can't pay the full amount, to minimize penalties and interest. Common mistakes include underestimating interest accrual and not realizing penalties apply even if you are due a refund but file late.

Example: Underpaid 2026 Taxes, Filed Late

  1. 1 Sarah owes $5,000 in taxes for 2026. The tax deadline was April 15, 2027. She filed her return on July 15, 2027 (3 months late) and paid the full $5,000 plus penalties and interest on the same day.
  2. 2 Failure-to-file penalty: 5% per month for 3 months = 15% of $5,000 = $750. Failure-to-pay penalty: 0.5% per month for 3 months = 1.5% of $5,000 = $75. Interest for 3 months at 8% annual rate on $5,000 is approximately $100.
  3. 3 Total estimated penalty and interest: $750 (failure-to-file) + $75 (failure-to-pay) + $100 (interest) = $925.
  4. 4 In this scenario, Sarah would owe an additional $925 on top of her original $5,000 tax liability due to late filing and payment. This example highlights the significant impact of penalties and interest, even over a relatively short period.

Source: IRS — Forms, Instructions & Publications · Last updated: April 2026

Frequently Asked Questions

What is the penalty for filing taxes late?
The failure-to-file penalty is 5% of the unpaid tax for each month (or part of a month) the return is late, up to a maximum of 25%. If the return is more than 60 days late, the minimum penalty is the lesser of $510 or 100% of the unpaid tax.
What is the penalty for paying taxes late?
The failure-to-pay penalty is 0.5% of the unpaid tax per month, up to a maximum of 25%. Interest also accrues on the unpaid balance at the federal short-term rate plus 3%, currently about 8% annually. Interest compounds daily.
Can IRS penalties be waived?
Yes. First-time penalty abatement is available if you had no penalties in the prior three years, filed all required returns, and paid or arranged to pay any tax due. You can also request reasonable cause abatement for circumstances like serious illness or natural disaster.

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