Missing a federal tax deadline can create three separate charges: a failure-to-file penalty, a failure-to-pay penalty and interest. They follow different rules and may apply at the same time. Understanding the distinction can help a taxpayer limit additional cost and respond appropriately.

1. Filing Late and Paying Late Are Different

The failure-to-file penalty is generally 5% of unpaid tax for each month or partial month a required return remains late, up to 25%. The base generally reflects tax required to be shown on the return, reduced by timely payments and applicable credits. If no tax remains unpaid, the standard percentage-based Form 1040 failure-to-file penalty may be zero, although other penalties can still apply in different situations.

The failure-to-pay penalty is generally 0.5% of unpaid tax for each month or partial month after the original payment deadline, also up to 25%. Interest is separate and generally accrues daily until the balance is paid.

The IRS changes interest rates quarterly. The 7% rate shown above applies to underpayments during July-September 2026 and should be updated if the article is published or refreshed in a later quarter.

2. When Both Penalties Apply

When both penalties apply in the same month, the IRS generally reduces the failure-to-file penalty by the failure-to-pay penalty for that month. The combined charge is therefore generally 5% for each of the first five months: 4.5% net failure-to-file plus 0.5% failure-to-pay. After the filing penalty stops, the payment penalty can continue until it reaches its own 25% cap. The maximum combined percentage can reach 47.5%, before interest.

Example: assume an individual owes $10,000, makes no payment and files six full months late. Ignoring interest and other adjustments, the approximate penalties are:

3. The More-Than-60-Day Minimum

For a return required to be filed in 2026 that is more than 60 days late, the minimum failure-to-file penalty is the smaller of $525 or 100% of the unpaid tax. The amount is adjusted periodically, so a future-year article should confirm the applicable figure rather than carrying forward the 2026 amount.

4. What Form 4868 Does—and Does Not Do

For most calendar-year individuals, a timely Form 4868 generally extends the filing deadline for six months. It does not extend the original deadline for paying tax. Unpaid tax may therefore continue to generate the failure-to-pay penalty and interest during the extension period.

The Form 4868 instructions provide a reasonable-cause presumption for the extension period when at least 90% of the total tax is paid by the original due date through withholding, estimated payments or an extension payment, and the remaining balance is paid with the return filed within the extension period. Falling below 90% does not create an automatic waiver; the penalty is calculated on the amount that remained unpaid from the original due date, subject to any other available relief.

5. If Full Payment Is Not Possible

A partial payment reduces the balance on which future failure-to-pay penalties and interest are calculated. Pay as much as reasonably possible by the original deadline and evaluate an IRS arrangement for the remainder.

• Short-term plan. Eligible individuals owing less than $100,000 in combined tax, penalties and interest may qualify for up to 180 days to pay. There is generally no setup fee, but penalties and interest continue.
• Simple installment agreement. Eligible individuals owing $50,000 or less may apply online for monthly payments. The approved term, payment method, fees and conditions depend on current IRS rules and the taxpayer’s situation.
• Offer in Compromise. Some taxpayers may qualify to settle for less than the full balance based on ability to pay, income, expenses and asset equity. Eligibility is strict.
• Currently Not Collectible status. The IRS may temporarily delay active collection when payment would prevent a taxpayer from meeting necessary living expenses. The debt remains, interest and penalties may continue, refunds may be applied and a federal tax lien may be filed.

6. Penalty Relief May Be Available

Reasonable-cause relief depends on the facts. The IRS generally considers whether the taxpayer exercised ordinary business care and prudence but could not comply because of circumstances such as serious illness, disaster, destruction of records or another documented event. Simple oversight, inability to pay by itself or relying on a preparer merely to remember the filing deadline generally does not establish reasonable cause.

Eligibility generally requires timely filing and payment history for the prior three years, or 12 consecutive quarters for quarterly returns. AEP does not apply to every return; information returns and certain event-driven returns are generally excluded. During the transition, First Time Abate may still be available for eligible periods not considered for AEP. For original returns due January 1, 2027 or later, AEP replaces First Time Abate. Neither program eliminates the underlying tax or statutory interest.

7. Business Returns Follow Different Rules

Do not apply the Form 1040 percentages mechanically to a partnership, S corporation, payroll return or information return. For example, a 2025 Form 1065 filed in 2026 may incur $255 for each month or partial month, multiplied by the number of partners, for up to 12 months. A partnership with 10 partners filing two months late could therefore face $5,100 before considering relief. S corporation, payroll-deposit, Forms W-2 and 1099, and international-reporting penalties have their own rules and can be substantial.

Sources and Professional Notes

• IRS: Failure to File Penalty
• IRS: Failure to Pay Penalty
• IRS Topic No. 653: Penalties and Interest
• IRS: Quarterly Interest Rates
• IRS Form 4868 and Instructions
• IRS: Payment Plans and Installment Agreements
• IRS: Administrative Penalty Relief and AEP
• IRS: 2025 Instructions for Form 1065

Prepared: August 2026  ·  Last technical review: August 2026  ·  Reviewed by: [PNJ reviewer]

Disclaimer

This article is for general informational purposes only and does not constitute tax, accounting or legal advice. Penalty calculations and relief depend on the return, taxpayer type, filing and payment history, notices received, payment dates and other facts. IRS amounts, eligibility standards and interest rates may change. Consult a qualified tax professional regarding a specific return or notice.