Penalties and Interest Calculator
Estimate selected federal failure-to-file and failure-to-pay penalties and interest. Review the limitations before relying on any result.
Testing release — limited scope. This calculator supports an illustrative Form 1040 late-file/late-pay estimate with IRS-published interest rates for 2017–2026. It does not calculate Form 2210, partnership/S corporation penalties, interest on penalties, statutory minimum FTF penalties, special relief, or every IRS exception. Do not use it as a final IRS payoff quote.
Tax information
Extension of time to file does not extend time to pay.
Used only if a valid extension was obtained.
After timely payments and credits; enter the balance subject to penalties.
Payments after the due date
Add each payment with its effective date. Payments reduce the outstanding balance for subsequent days.
IRS regular underpayment rates are selected automatically by date (2017–2026), including changes between quarters. IRS rate source. No rate entry required.
Calculation Results Summary
Failure-to-file penalty (illustrative)$0.00Failure-to-pay penalty (illustrative)$0.00Interest on unpaid tax (daily compounding)$0.00Estimated unpaid tax$0.00Estimated subtotal$0.00
Calculation methodology and details
The subtotal excludes interest on penalties, minimum late-filing penalties and other assessments. It is not an official IRS balance.