The Failure-to-File Penalty
If you owe taxes and don’t file by the deadline (including extension), the IRS charges a failure-to-file penalty of 5% of the unpaid tax per month (or partial month), up to a maximum of 25% of the unpaid balance.
If you also fail to pay, both penalties apply — but they are capped:
- Failure to file: 5% per month (up to 25%)
- Failure to pay: 0.5% per month (up to 25%)
- Combined maximum: 47.5%
Interest Charges
In addition to penalties, the IRS charges interest on unpaid taxes at the federal short-term rate plus 3 percentage points — compounding daily. In 2025, this rate is approximately 8% annualized.
What If You’re Due a Refund?
If you’re owed a refund and don’t file, there is no late-filing penalty. However, there is a 3-year statute of limitations on claiming refunds — after 3 years, the refund is forfeited to the Treasury.
The 3-Year and 10-Year Rules
- IRS has 3 years to audit your return (from filing date)
- No statute of limitations if you never file — the IRS can assess tax years later
- 10 years to collect taxes once assessed
Can Not Filing Be Criminal?
Yes, in extreme cases. Tax evasion (willfully failing to file with intent to evade) can result in criminal charges. This is rare and reserved for flagrant, repeated non-filers with significant tax liability.
What to Do If You Haven’t Filed
File as soon as possible — even years late. The IRS has a Voluntary Disclosure Program and First-Time Penalty Abatement policy that can significantly reduce penalties for good-faith late filers. You can also enter an Installment Agreement if you can’t pay the full balance.