Estate Tax Calculator

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Estate Tax Calculator

Estimate federal estate tax owed based on the 2026 exemption amount of $15 million per individual.

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ESTIMATED FEDERAL ESTATE TAX
$0
Available exemption$0
Taxable amount (over exemption)$0
Effective rate on taxable amount40%
Net to heirs (before other deductions)$0
Disclaimer: This calculator uses the 2026 federal estate tax exemption ($15 million per individual) for informational and educational purposes only and does not constitute legal or tax advice. It applies a simplified flat 40% rate and excludes state estate taxes, deductions, and portability filing requirements. Consult an estate planning attorney or tax professional for guidance on your specific situation.

Estate Tax Calculator: Formula, Worked Examples & Complete Guide

Written by Mathew | Financial Tools & Calculation Specialist · Last updated July 31, 2026

In two sentences: An estate tax calculator estimates federal estate tax owed by subtracting the 2026 exemption of $15 million per individual ($30 million per married couple) from the total estate value, then applying a 40% tax rate to whatever remains. This guide breaks down the formula, the portability rule that lets married couples combine exemptions, and worked examples showing exactly when an estate actually owes federal tax.

What Is an Estate Tax Calculator?

An estate tax calculator estimates how much federal estate tax a person’s estate will owe based on its total value at death, after applying the current lifetime exemption. Because the exemption is so large, the federal estate tax only affects a small percentage of estates — but for those it does affect, the tax rate is substantial.

The Estate Tax Calculator Formula

Taxable Estate = Total Estate Value − Federal Exemption
Estate Tax Owed = Taxable Estate × 40% (for amounts above the exemption)

2026 Federal Estate Tax Exemption

The federal estate and gift tax exemption for 2026 is $15 million per individual, up from $13.99 million in 2025. This increase, made permanent under the One Big Beautiful Bill Act (OBBBA), removes a previously scheduled reduction and sets the exemption to continue adjusting for inflation going forward. Estates below this threshold owe no federal estate tax at all. For amounts above the exemption, the federal estate tax rate is a flat 40%.

Portability: doubling the exemption for married couples

Since 2011, the estate tax exclusion has been portable between spouses. If one spouse dies without using their full $15 million exemption, the surviving spouse can elect portability to add the deceased spouse’s unused exemption to their own — potentially protecting up to $30 million combined from federal estate tax. This portability isn’t automatic; it requires filing an estate tax return (Form 706) even if no tax is owed, specifically to elect portability and preserve the unused exemption for the surviving spouse.

Worked Examples

Example 1: An estate well under the exemption

An individual dies in 2026 with a total estate valued at $8 million.

Taxable Estate = $8,000,000 − $15,000,000 = negative (no tax owed)

Since the estate falls entirely below the $15 million exemption, no federal estate tax is due, regardless of how the assets are structured.

Example 2: An estate exceeding the individual exemption

An individual dies in 2026 with a total estate valued at $17 million.

Taxable Estate = $17,000,000 − $15,000,000 = $2,000,000
Estate Tax Owed = $2,000,000 × 0.40 = $800,000

Example 3: A married couple using portability

A married couple has a combined estate of $22 million. The first spouse dies, using none of their $15 million exemption (all assets pass to the surviving spouse tax-free under the unlimited marital deduction). The surviving spouse elects portability, then later dies with the full $22 million estate.

Combined Exemption (with portability) = $15,000,000 (deceased spouse's unused) + $15,000,000 (surviving spouse's own) = $30,000,000
Taxable Estate = $22,000,000 − $30,000,000 = negative (no tax owed)

Without portability, the surviving spouse’s estate would only have their own $15 million exemption to apply against the full $22 million, creating a taxable estate of $7 million and roughly $2.8 million in estate tax — portability alone eliminates the entire tax bill in this scenario.

Example 4: A large estate above the combined exemption

A married couple’s combined estate is $35 million, with portability properly elected.

Taxable Estate = $35,000,000 − $30,000,000 = $5,000,000
Estate Tax Owed = $5,000,000 × 0.40 = $2,000,000

Step-by-Step: How to Use an Estate Tax Calculator

  1. Total the fair market value of all estate assets at death — real estate, financial accounts, retirement accounts, business interests, life insurance proceeds (if owned by the decedent), and personal property.
  2. Subtract any allowable deductions, such as debts, funeral expenses, and charitable bequests.
  3. Subtract the applicable federal exemption ($15 million for an individual in 2026, or up to $30 million for a married couple with portability properly elected).
  4. Apply the 40% federal estate tax rate to any remaining taxable amount.
  5. Check whether your state imposes its own separate estate or inheritance tax, since many states have far lower exemption thresholds than the federal amount.

State Estate Taxes: A Separate Consideration

An estate tax calculator focused on federal tax doesn’t capture the full picture for residents of certain states. Some states impose their own estate tax with exemption amounts far below the generous federal threshold — for instance, Massachusetts has a state estate tax exemption of just $2 million, not indexed for inflation, meaning a family with an $8 million estate could owe zero federal estate tax but still face a real state-level bill. A handful of states also impose a separate inheritance tax, which is levied on heirs rather than the estate itself and can carry very small exemptions for distant relatives.

What Counts Toward Your Taxable Estate

  • Real estate — including a primary residence and any additional properties, valued at fair market value at death.
  • Financial accounts — bank accounts, brokerage accounts, and other investment holdings.
  • Retirement accounts — 401(k)s, IRAs, and similar accounts count toward estate value, separate from any income tax owed by beneficiaries on withdrawals.
  • Life insurance proceeds — included in the taxable estate if the decedent owned the policy, even though beneficiaries generally don’t pay income tax on the payout itself.
  • Business interests — the value of any owned business or partnership stake, which can require professional valuation.

Using an Estate Tax Calculator for Proactive Planning

An estate tax calculator is most useful well before it’s actually needed — running projections years in advance gives families time to implement strategies that a last-minute calculation simply can’t accommodate.

Strategies an estate tax calculator can help evaluate

  • Lifetime gifting versus waiting until death. Since the gift tax and estate tax exemption are unified, an estate tax calculator can model how strategic lifetime gifts (using the separate $19,000 annual exclusion per recipient) might reduce a future taxable estate without touching the larger lifetime exemption at all.
  • Whether a credit shelter trust makes sense. For couples concerned about relying solely on portability, an estate tax calculator can help illustrate the difference between a portability-only approach and a trust-based strategy that locks in the first spouse’s exemption more permanently.
  • Projecting future estate growth. Running an estate tax calculator with a projected asset growth rate over 10-20 years helps families see whether an estate currently under the exemption might eventually grow into taxable territory, prompting earlier planning.
  • State-level exposure alongside federal exemption. An estate tax calculator focused only on the generous federal exemption can create false confidence for families in states with much lower state-level exemption thresholds, so checking both figures together matters.

Frequently Asked Questions

Do most estates actually owe federal estate tax?

No — because the exemption is so high ($15 million per individual in 2026), only a small percentage of the wealthiest American estates owe any federal estate tax at all.

What happens if I don’t file for portability when my spouse dies?

You lose the ability to add their unused exemption to your own, which could mean your estate faces tax on assets that portability would have shielded entirely. Filing Form 706 to elect portability is worthwhile even when no tax is currently due, specifically to preserve this option.

Is the estate tax exemption the same as the gift tax exemption?

Yes — the federal estate and gift tax exemption is unified, meaning $15 million in 2026 covers both lifetime gifts and transfers at death combined, not $15 million for each separately.

Do all states have an estate tax?

No — most states have no separate estate tax, relying entirely on the federal system. A handful of states, mostly in the Northeast, impose their own state-level estate tax with exemptions well below the federal amount.

Related Calculators

In summary, an estate tax calculator shows that the federal estate tax only affects the wealthiest estates given the generous $15 million (or $30 million with portability) 2026 exemption, but understanding the portability election and any separate state-level estate tax remains essential for accurate planning.

About the author: Mathew is a Financial Tools & Calculation Specialist focused on building and fact-checking online calculators across personal finance and estate planning topics.

Note: This calculator and article are provided for general educational and informational purposes only and do not constitute legal or tax advice. Estate tax rules are complex and vary by state. Consult a qualified estate planning attorney or tax professional for guidance specific to your situation.