How the failure-to-file penalty works

When you file a federal return after its deadline and still owe tax, the IRS adds a failure-to-file penalty under IRC §6651(a)(1). It is 5% of the unpaid tax for each month or part of a month the return is late, capped at 25%. A single day into a new month counts as a whole month, so the penalty climbs in 5% steps and reaches its maximum after five months.

IRS Code Section
IRC §6651(a)(1)
Penalty Rate
5% of unpaid tax per month (or part of a month)
Maximum
25% of the unpaid tax
Minimum (over 60 days late)
Lesser of $525 or 100% of the tax (2026)
When Reduced
Drops to 4.5%/mo in months a failure-to-pay penalty also applies
Common Relief
First-time abatement · Reasonable cause (Form 843)

The penalty is calculated on the tax that remained unpaid as of the filing deadline — not on your total tax bill. If you paid most of what you owed through withholding, the penalty base is only the remainder.

— File even if you can't pay —

The failure-to-file penalty is ten times the failure-to-pay penalty each month. Filing on time — or getting an extension — stops the larger penalty even when you can't pay the balance. If a return is already late, filing now stops the 5% clock immediately.

Getting the penalty removed

The failure-to-file penalty is among the most frequently abated. Taxpayers with a clean three-year history often qualify for first-time abatement, and those with a legitimate hardship can use reasonable cause. If you have already paid the penalty, Form 843 recovers it — along with the interest the IRS charged on it — as a refund.

Use the calculator to size the penalty, then start a free review. We pull your IRS transcripts, confirm exactly what was assessed, and handle the abatement on a contingency basis.