Federal Estate Tax Calculator

The federal exemption is $15M per person in 2026 (made permanent by OBBBA 2025), with a top rate of 40%. The marital deduction to a U.S.-citizen spouse is unlimited and defers tax. Use the portability field to add a deceased spouse’s unused exclusion.

Federal Estate Tax Calculator — Calculation Summary

Input / parameter	Value
Taxable estate	$20,000,000
Portability add-on (DSUE)	$0
Result
Effective exemption	$15,000,000
Taxable amount (over exemption)	$5,000,000
Federal estate tax	$1,945,800
Effective rate on estate	9.7%

Source: IRC § 2010; IRS Revenue Procedure 2025-32 (2026 brackets).

This is an informal planning estimate only, not legal or tax advice. Confirm all figures with the IRS, your state Department of Revenue, or a licensed estate attorney or CPA before relying on them.

Taxable estate ($)Portability add-on — deceased spouse's unused exclusion ($)

Effective exemption$15,000,000

Taxable amount (over exemption)$5,000,000

Federal estate tax$1,945,800

Effective rate on estate9.7%

Top federal rate 40% above the exemption. Marital deduction to a U.S.-citizen spouse is unlimited and defers tax. GST exemption is also $15M (non-portable). Figures use the exact IRS graduated brackets.

Informal estimate only — not legal or tax advice. Figures cite federal statute (IRC § 2010, OBBBA 2025) and each state's Department of Revenue. Tax laws and exemption amounts change yearly; confirm the current rule with the IRS, your state agency, or a licensed estate attorney or CPA before relying on any number.

How this calculator works

Use this free federal estate tax calculator to estimate what a taxable estate will owe above the 2026 exemption. The tool starts with the $15 million federal estate tax exemption per person, subtracts the exemption from the estate, and applies the exact IRS graduated brackets to the excess. For married couples, you can add a deceased spouse’s unused exclusion (DSUE) to model portability.

Calculation method & sources

Federal exemption: IRC § 2010(c)(3) and IRS Revenue Procedure 2025-32 set the 2026 basic exclusion amount at $15,000,000 per person. The One Big Beautiful Bill Act (OBBBA 2025, Pub. L. 119-21) made the higher exemption permanent and indexed it for inflation starting in 2027.
Rate schedule: IRC § 2001 provides the graduated estate tax brackets from 18% to a top rate of 40% on taxable amounts over $1,000,000.
Portability (DSUE): IRC § 2010(c)(5). A surviving spouse can elect to use the deceased spouse’s unused exclusion by filing IRS Form 706 within 9 months of death (plus a possible 6-month extension).
Marital deduction: IRC § 2056 allows an unlimited deduction for transfers to a surviving spouse who is a U.S. citizen. It defers tax until the second death rather than eliminating it.

How to interpret your federal estate tax result

A result of $0 means the taxable estate is at or below the effective exemption you entered (including any portability add-on).
The “taxable amount over exemption” is the portion actually exposed to the graduated brackets.
Portability only helps if the estate of the first spouse timely files Form 706 to elect it; it is not automatic.
The “effective rate on estate” is the tax divided by the full estate — it is usually far below the 40% top marginal rate.
This calculator covers federal tax only. State estate or inheritance taxes are calculated separately in our By-State and Inheritance tools.

Related guides

Frequently asked questions

What is the federal estate tax exemption in 2026?

The 2026 federal estate tax exemption is $15 million per person, or $30 million for a married couple that elects portability. OBBBA 2025 made the amount permanent and indexed it for inflation.

How does portability of a deceased spouse’s unused exemption work?

Portability lets a surviving spouse add the deceased spouse’s unused federal estate tax exemption to their own. The executor must file IRS Form 706 and affirmatively elect portability, generally within 9 months of death.

What is the estate tax rate above the exemption?

Federal estate tax uses graduated brackets starting at 18% and rising to 40% on taxable amounts over $1,000,000 above the exemption.

Does the marital deduction reduce federal estate tax?

Yes. Transfers to a surviving U.S.-citizen spouse qualify for an unlimited marital deduction under IRC § 2056. The tax is deferred until the surviving spouse dies, unless further planning is used.

Is the $15M estate tax exemption permanent?

As of 2026, the $15 million exemption is permanent under the One Big Beautiful Bill Act. It is indexed for inflation beginning in 2027, though Congress could change the law in the future.

Who actually pays federal estate tax?

Only estates with a taxable value above the exemption owe federal estate tax. In 2026, that means individuals above $15M and married couples above $30M (with portability).

Not legal or tax advice. This estimate follows the federal and state statutes referenced on this page but cannot capture every factor (trusts, business valuation, charitable deductions, prior gifts, state add-backs).