US Late Filing Penalty Calculator

The failure-to-file penalty is 5% of the unpaid tax for each month or part month the return is late, capped at 25% — so it reaches its maximum after five months. It is calculated on the tax still unpaid at the original due date, which means a return filed late with no balance owing generally carries no failure-to-file penalty at all.

The failure-to-pay penalty is 0.5% of the unpaid tax for each month or part month the tax remains outstanding, also capped at 25%. Because it accrues at a tenth of the filing penalty rate but runs for far longer, it can continue building for years after the failure-to-file penalty has already maxed out.

They do not simply stack. For any month in which both run, the failure-to-file penalty is reduced by the failure-to-pay penalty for that month, so the combined charge is 5% per month rather than 5.5%. Over the first five months this produces 22.5% failure-to-file plus 2.5% failure-to-pay, and the failure-to-pay penalty then continues alone.

Almost always, yes. Filing on time and paying late exposes you to the 0.5% monthly failure-to-pay penalty. Filing late as well adds the 5% monthly failure-to-file penalty on top — ten times the rate. Filing the return by the deadline, or extending it properly, is the cheapest single action available when funds are short.

No. Form 4868 extends the time to file, not the time to pay. Tax remains due on the original deadline, and interest and the failure-to-pay penalty run from that date on anything unpaid. A valid extension does, however, stop the much larger failure-to-file penalty from accruing while the return is outstanding.

US citizens and residents living outside the United States get an automatic two-month extension to 15 June, and can extend further to 15 October with Form 4868. Interest still runs from the ordinary April deadline on any unpaid tax. The FBAR is separately due 15 April with an automatic extension to 15 October that requires no request.

Yes. Where a return is filed more than 60 days after its due date, a minimum failure-to-file penalty applies, set as the lesser of a fixed statutory amount or 100% of the tax required to be shown on the return. The fixed amount is adjusted for inflation, so confirm the figure applying to your filing year before relying on it.

Yes. Interest runs on underpaid tax from the original due date until it is paid, and it is also charged on the penalties themselves. The underpayment rate is set quarterly and is generally the federal short-term rate plus three percentage points for individuals, so the effective cost of delay changes through the year.

IRS policy generally limits enforcement of delinquent filing to the six most recent years, subject to managerial discretion to go further. That is an administrative practice, not a statutory limit — there is no assessment deadline at all for a year in which no return was ever filed, so an unfiled year stays permanently open.

For qualifying non-willful taxpayers, yes. The Streamlined Foreign Offshore Procedures waive failure-to-file, failure-to-pay, accuracy-related, information return and FBAR penalties for those meeting the non-residency test. Tax and statutory interest remain payable. The domestic version instead applies a 5% miscellaneous offshore penalty.

First Time Abate has historically removed failure-to-file and failure-to-pay penalties for taxpayers with a clean prior compliance history. The IRS has announced an automatic penalty exemption that replaces it for returns with original due dates from 1 January 2027. Neither route generally covers international information return penalties, which is what usually bites on a cross-border catch-up.

Penalties can be abated where the failure was due to reasonable cause and not willful neglect — serious illness, death in the family, destruction of records, or reliance on incorrect professional advice in some circumstances. Reasonable cause is assessed on the specific facts, and lack of funds alone is rarely sufficient without the circumstances that caused it.

No, and this is the trap on cross-border cases. Penalties for missed Forms 5471, 8938, 3520 and the FBAR are separate fixed-dollar regimes, not percentages of tax. They can apply even where no tax is owed, and the assessment period for the whole return can stay open under IRC section 6501(c)(8) until the required information return is filed.

The failure-to-file and failure-to-pay penalties are calculated on unpaid tax, so a refund year generally carries neither. The real cost is losing the refund itself: a claim for credit or refund must usually be made within three years of filing or two years of payment, after which the money cannot be recovered.

It applies the 5% monthly failure-to-file penalty capped at 25%, the 0.5% monthly failure-to-pay penalty capped at 25%, the reduction of the filing penalty in months where both run, and simple interest on the unpaid tax at the rate you enter. It is an estimate for orientation only, and does not model the more-than-60-days minimum penalty, abatement, or information return penalties.