IRS penalty and interest calculator

How the IRS adds it up

• Failure to file: 5% of the unpaid tax for each month or part of a month late, up to 25%.
• Failure to pay: 0.5% a month, up to 25%. It drops to 0.25% a month on a payment plan if you filed on time, and goes up to 1% a month if you don't pay within 10 days of a notice of intent to levy.
• In a month when both apply, the failure to file penalty is cut by the failure to pay amount.
• For returns due after Dec 31, 2025 that are over 60 days late, the smallest failure to file penalty is $525 or 100% of the tax, whichever is less.
• Interest is 7% a year for individuals in Q4 2026, compounded daily. It also grows on penalties.

Can penalties come off?

Sometimes. The IRS has first time relief for people with a clean record and relief for a good reason, like a serious illness. Interest usually stays. Read our answers.

Results depend on your situation. Not every case qualifies.

This is an estimate based on public IRS rules and rates as of October 1, 2026. Your IRS notice or online account shows your real balance.

How this penalty calculator works

The late filing penalty is 5% of the unpaid tax for each month or part of a month late, up to 25%. If a return due after Dec 31, 2025 is more than 60 days late, the minimum is $525 or the full tax, whichever is less.

The late payment penalty is 0.5% a month, up to 25%. It drops to 0.25% a month on an approved plan if you filed on time. It rises to 1% a month if you don't pay within 10 days of a notice of intent to levy.

When both apply in the same month, the late filing penalty is cut by the late payment amount. Interest is added on top, at 7% a year for individuals, compounded daily, in the fourth quarter of 2026.

This is an estimate based on public IRS rules and rates. Your IRS notice or online account shows your real balance.

Common questions