How Estate Tax Penalties Are Calculated
Estate tax penalties under IRC § 6651 are calculated based on the unpaid tax and the length of delay. Here's how each penalty works:
- 1Failure-to-File (FTF): 5% of unpaid tax per month or partial month late, up to 25% maximum.
- 2Failure-to-Pay (FTP): 0.5% of unpaid tax per month, up to 25% maximum. Reduced to 0.25% if on installment agreement.
- 3Combined Penalty Cap: When both penalties apply in the same month, combined rate is capped at 5% (FTF reduced by FTP).
- 4No Minimum Penalty: The 60-days-late minimum FTF penalty under IRC § 6651(a) applies only to income tax returns. It does not apply to Form 706.
Example Calculation
Situation
- Gross estate: $15,000,000
- Exemption (2025): $13,990,000
- Estate tax due: $204,000
- Date of death: January 15, 2025
- Due date: October 15, 2025
- Filed: January 20, 2026 (3 months late)
Penalty Breakdown
- FTF: $204,000 x 5% x 3 = $30,600
- FTP: $204,000 x 0.5% x 3 = $3,060
- But combined cap applies:
- FTF: $204,000 x 4.5% x 3 = $27,540
- FTP: $204,000 x 0.5% x 3 = $3,060
- Total: $30,600
2026 Estate Tax Thresholds
| Threshold | Amount | Notes |
|---|---|---|
| Estate Tax Exemption | $15,000,000 | Per person (indexed for inflation) |
| Form 706 Filing Threshold | $15,000,000 | Must file if gross estate exceeds this |
| Top Tax Rate | 40% | On taxable estate above exemption |
| Married Couple (with Portability) | $30,000,000 | Combined exemption if portability elected |
| Minimum Late Filing Penalty | N/A | Does not apply to Form 706 (income tax returns only) |
Portability: Double Your Exemption
Portability allows a surviving spouse to inherit the deceased spouse's unused estate tax exemption (DSUE). This can effectively double the amount shielded from estate tax.
Requirements:
- File Form 706 within 9 months of death (or 15 months with extension)
- Form 706 must be filed even if no estate tax is due
- Late portability election available within 5 years of death (Rev. Proc. 2022-32)
Note: Filing solely for portability carries no penalty since there's no tax due. Don't miss this opportunity to preserve the exemption for the surviving spouse.
How to Get Estate Tax Penalties Abated
First-Time Abatement (FTA)
Get FTF and FTP penalties waived if you have a clean 3-year compliance history. Free to request, no documentation required.
Learn about FTA →Reasonable Cause
Penalties may be abated if you can demonstrate reasonable cause: serious illness, death in family, fire/casualty, or inability to obtain records.
Use Form 843 to requestCalculate Your Estate Tax Penalty
Free calculator with FTF, FTP, and valuation misstatement calculations
Start Calculator →Estate Tax Penalty FAQs
Form 706 (Estate Tax Return) is due 9 months after the date of death. For example, if the decedent died on January 15, 2025, the return is due October 15, 2025. An automatic 6-month extension is available by filing Form 4768.
The federal estate tax exemption is $15,000,000 per person for deaths in 2026 (P.L. 119-21; Rev. Proc. 2025-32) and $15,480,000 for 2027 (Rev. Proc. 2026-35). For 2025 it was $13,990,000. Estates valued at or below the exemption owe no federal estate tax. Married couples can potentially shield up to $30 million in 2026 through portability.
The failure-to-file (FTF) penalty is 5% of the unpaid tax for each month the return is late, up to a maximum of 25%. The 60-days-late minimum penalty applies only to income tax returns, not to Form 706.
Yes, the failure-to-pay (FTP) penalty is 0.5% of the unpaid tax per month, up to 25% maximum. This is separate from interest charges. If both FTF and FTP apply, the combined monthly rate is capped at 5%.
Portability allows a surviving spouse to use any unused estate tax exemption from their deceased spouse (called DSUE - Deceased Spousal Unused Exclusion). To elect portability, you must file a timely Form 706 within 9 months of death (or 15 months with extension), even if no tax is owed.
Yes, penalties may be abated through First-Time Penalty Abatement (FTA) if you have a clean 3-year compliance history, or through reasonable cause if circumstances beyond your control prevented timely filing or payment.