Tax Extension Penalty Calculator
Calculate penalties and interest for filing taxes late.
See the cost of failure-to-file and failure-to-pay penalties.
Your data stays in your browser. We do not store, collect, or transmit any information you enter.
Penalty Estimate
IRS penalties for late filing and late payment are separate.
Failure-to-File Penalty:
- 5% of unpaid tax per month (or partial month), up to 25%
- Minimum penalty of $485 (or 100% of tax owed) if more than 60 days late
Failure-to-Pay Penalty:
- 0.5% of unpaid tax per month, up to 25%
- Reduced to 0.25%/month if you filed on time and set up a payment plan
Interest:
- Currently ~8% annual rate (compounds daily)
- Charged on unpaid tax plus penalties
If you filed an extension: You avoid the failure-to-file penalty, but still owe failure-to-pay penalty and interest on any unpaid balance.
Rates and minimums based on 2024 IRS rules.