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For planning only — not tax advice. Estate tax rules change often; consult a tax professional.
Estimating federal estate tax takes less than a minute with this calculator, but the quality of the answer depends entirely on the quality of the numbers you enter. Before you begin, gather a rough inventory of the estate: the fair market value of the major assets, the outstanding debts, and the federal exemption amount for the year of death. With those three figures in hand, follow the steps below.
Step 1 — Enter the gross estate. Type the total fair market value of everything the decedent owned or had certain interests in at death. That includes real estate, bank and brokerage accounts, retirement accounts such as IRAs and 401(k)s, business interests, vehicles, art and collectibles, and any life insurance policies the decedent personally owned. Do not subtract mortgages or other debts at this stage; the calculator handles that separately in Step 2.
Step 2 — Enter debts and expenses. Add up mortgages, home-equity loans, auto loans, credit-card balances, and any other liabilities, plus a realistic estimate of funeral costs, executor and attorney fees, and other estate administration expenses. Debts and deductible expenses shrink the estate before the tax is calculated, so leaving them out will overstate the tax.
Step 3 — Enter the exemption amount. The field is pre-filled with $13,610,000, the 2024 federal basic exclusion amount. Exemptions are adjusted every year, so type the figure that matches your situation: 13,990,000 for a 2025 death, or 15,000,000 per person for 2026 under current law. Using the wrong year's exemption is the single most common reason estimates come out wrong.
Step 4 — Click "Estimate Estate Tax" and read the four results. The calculator shows the estimated federal estate tax, the adjusted gross estate (gross estate minus debts and expenses), the taxable estate (the amount left above the exemption), and approximately what heirs receive after the tax is paid. A quick sanity check with the default figures: a $15,000,000 gross estate minus $1,000,000 in debts gives an adjusted gross estate of $14,000,000. Subtract the $13,610,000 exemption and the taxable estate is $390,000. At the flat 40% federal rate, the estimated tax is $156,000, so heirs receive roughly $15,000,000 − $156,000 = $14,844,000.
The federal estate tax is a transfer tax imposed on the privilege of passing property at death. It is paid by the estate itself — the executor settles it from estate assets before anything is distributed — not by the individual heirs. Only estates whose taxable value exceeds the federal exemption owe anything at all, which is why the overwhelming majority of American estates pay zero federal estate tax. When tax is due, the estate files IRS Form 706, generally within nine months of the date of death, with a six-month extension available on request.
The basic exclusion amount, usually just called the exemption, is the dollar value that passes free of federal estate and gift tax. It was $13,610,000 per person in 2024 and $13,990,000 per person in 2025. For 2026, legislation signed in 2025 permanently set the exemption at $15,000,000 per person, indexed for inflation, ending the uncertainty around the scheduled sunset of the 2017 tax cuts. Because the exemption moves every year, always confirm the figure for the year of death rather than relying on memory.
Several related concepts matter for understanding the result. The gross estate is everything included for tax purposes, valued at fair market value on the date of death (or, if elected, on the alternate valuation date six months later). The adjusted gross estate is the gross estate minus allowable debts, funeral costs, and administration expenses. The taxable estate is what remains after subtracting the exemption and any marital or charitable deductions — this is the amount the 40% rate actually applies to. The unified credit is the tax credit that shelters the exemption amount, and the gift tax and estate tax share one unified system, so large lifetime gifts reduce the exemption available at death. Portability lets a surviving spouse inherit the deceased spousal unused exclusion (DSUE) — the part of the first spouse's exemption that went unused — effectively doubling the couple's shelter, but only if the executor files Form 706 to elect it. Heirs also benefit from a step-up in basis, which resets the cost basis of inherited capital assets to their date-of-death value and can wipe out years of unrealized capital gains. Two companion transfer taxes exist alongside the estate tax: the gift tax on large lifetime transfers and the generation-skipping transfer tax on transfers to grandchildren and beyond.
The federal tax is only part of the picture. Roughly a dozen states plus the District of Columbia impose their own estate or inheritance taxes, often with far lower exemptions — around $1,000,000 in Oregon and $2,000,000 in Massachusetts, for example. An estate that owes nothing federally can still owe a meaningful amount to a state, so this calculator's federal-only estimate should always be paired with a check of state rules.
The math behind the calculator is a short chain of subtractions followed by one multiplication. First the debts come off the gross estate, then the exemption comes off the result, and the flat 40% federal rate applies to whatever is left:
Adjusted gross estate = Gross estate − Debts and expenses
Taxable estate = Adjusted gross estate − Exemption (if negative, the taxable estate is $0)
Federal estate tax = Taxable estate × 40%
Heirs receive ≈ Gross estate − Federal estate tax
Worked example 1. A decedent leaves a gross estate of $15,000,000 and owed $1,000,000 in mortgage and other debts at death. The 2024 exemption of $13,610,000 applies. Adjusted gross estate = $15,000,000 − $1,000,000 = $14,000,000. Taxable estate = $14,000,000 − $13,610,000 = $390,000. Federal estate tax = $390,000 × 0.40 = $156,000. Heirs receive approximately $15,000,000 − $156,000 = $14,844,000. Notice how only $390,000 of a $15,000,000 estate is actually exposed to tax — the exemption does almost all of the work.
Worked example 2. A business owner dies in 2025 with a gross estate of $25,000,000, debts and administration expenses of $2,500,000, and the 2025 exemption of $13,990,000. Adjusted gross estate = $25,000,000 − $2,500,000 = $22,500,000. Taxable estate = $22,500,000 − $13,990,000 = $8,510,000. Federal estate tax = $8,510,000 × 0.40 = $3,404,000. Heirs receive approximately $25,000,000 − $3,404,000 = $21,596,000. The effective rate on the whole estate is $3,404,000 ÷ $25,000,000 = 13.6%, well below the 40% statutory rate, because the exemption shelters the first $13,990,000.
Margaret, age 68 and widowed, dies in 2025. Her assets at fair market value: a primary home worth $4,200,000, a brokerage account worth $9,800,000, a traditional IRA worth $3,100,000, a minority interest in the family business appraised at $2,400,000, and a $500,000 life insurance policy she owned on her own life. Her gross estate totals $4,200,000 + $9,800,000 + $3,100,000 + $2,400,000 + $500,000 = $20,000,000. She owed $650,000 on her mortgage and $50,000 in credit-card and other balances, so debts and expenses come to $700,000.
Applying the 2025 exemption of $13,990,000: adjusted gross estate = $20,000,000 − $700,000 = $19,300,000. Taxable estate = $19,300,000 − $13,990,000 = $5,310,000. Federal estate tax = $5,310,000 × 0.40 = $2,124,000. Her heirs receive roughly $20,000,000 − $2,124,000 = $17,876,000, an effective rate of 10.62% on the gross estate.
The practical challenge for Margaret's executor is liquidity, not just arithmetic. The $2,124,000 tax bill is generally due within nine months of death, yet most of the estate sits in a house, a business interest, and a brokerage account. The executor may need to sell securities, take distributions from the IRA (which themselves trigger income tax), or arrange an installment agreement with the IRS. This is exactly why estate planners urge clients with estates near or above the exemption to keep a liquidity plan — life insurance inside an irrevocable trust, a securities portfolio that can be tapped quickly, or a line of credit — so the tax does not force a fire sale of the family home or business.
James and Priya, married, hold a combined $30,000,000 in assets. James dies first in 2025 with $12,000,000 titled in his own name — comfortably below his $13,990,000 exemption, so his estate owes no tax. Crucially, his executor files Form 706 and elects portability, transferring James's entire unused exclusion of $13,990,000 to Priya as DSUE. Many families skip this return because "no tax was owed," permanently forfeiting the extra shelter.
Priya dies in 2026, when the combined estate is worth $30,000,000 with $1,000,000 in debts and expenses. Her available exemption is her own 2026 amount of $15,000,000 plus the $13,990,000 DSUE from James, for a total shelter of $28,990,000. Adjusted gross estate = $30,000,000 − $1,000,000 = $29,000,000. Taxable estate = $29,000,000 − $28,990,000 = $10,000. Federal estate tax = $10,000 × 0.40 = $4,000. The children receive roughly $30,000,000 − $4,000 = $29,996,000.
Contrast that with the same facts but no portability election: Priya's exemption would be only her own $15,000,000, giving a taxable estate of $29,000,000 − $15,000,000 = $14,000,000 and a tax bill of $5,600,000. The single act of filing Form 706 after James's death saves the family approximately $5,596,000. Portability does not replace lifetime planning — trusts, annual gifts within the yearly exclusion (for example, $19,000 per recipient in 2025), and charitable strategies still matter — but it is the highest-value, lowest-cost move most married couples can make.
1. Using an outdated exemption figure. Someone who remembers the 2024 exemption of $13,610,000 and applies it to a 2026 death will overstate the tax badly. On a $15,000,000 debt-free estate, the old figure produces a taxable estate of $1,390,000 and a phantom tax bill of $556,000, while the correct 2026 exemption of $15,000,000 produces zero tax. Always type the exemption for the actual year of death.
2. Forgetting that decedent-owned life insurance counts. A $1,000,000 life insurance policy the decedent owned is part of the gross estate and can add $400,000 of federal tax at the 40% rate, even though the family thinks of it as "tax-free insurance money." Policies owned by an irrevocable life insurance trust (ILIT), by contrast, are generally excluded — ownership, not who receives the payout, is what matters.
3. Ignoring state estate and inheritance taxes. This calculator estimates the federal tax only. With state exemptions as low as $1,000,000 in Oregon and $2,000,000 in Massachusetts, a $5,000,000 estate can owe nothing federally yet face a six-figure state bill. About a dozen states plus the District of Columbia levy these taxes, and their rates, exemptions, and deduction rules all differ from the federal system.
4. Missing the portability election. When the first spouse dies owing no tax, families often see no reason to file Form 706 — and silently lose the deceased spouse's unused exclusion. As the example above shows, that omission can cost millions. The return electing portability is due nine months after death (plus a six-month extension), and late-election relief exists but is narrower and more expensive than filing on time.
5. Confusing the probate estate with the taxable estate. Assets that pass outside probate — joint accounts with survivorship rights, retirement accounts with named beneficiaries, and most trust assets — skip probate but are still included in the gross estate for tax purposes. The reverse error is just as common: valuing property at its original purchase price instead of its fair market value at death, which understates the gross estate and produces a falsely comforting estimate.
Estate tax planning touches several other calculations. Use our Investment Calculator to project how the estate's portfolio might grow over the years until it transfers, or browse all Financial Calculators for tools covering loans, savings, retirement, and more.
This page provides an estate tax calculator that estimates United States federal estate tax. Inputs: gross estate in dollars, debts and expenses in dollars, and the federal exemption (basic exclusion amount) in dollars, defaulting to $13,610,000 (2024). Outputs: estimated federal estate tax, adjusted gross estate, taxable estate, and approximate amount heirs receive. Method: adjusted gross estate equals gross estate minus debts and expenses; taxable estate equals adjusted gross estate minus exemption, floored at zero; federal estate tax equals taxable estate multiplied by the flat 40% rate; heirs receive approximately the gross estate minus the tax. Key facts: 2024 exemption $13,610,000; 2025 exemption $13,990,000; 2026 exemption $15,000,000 per person, portable between spouses via a Form 706 portability election; Form 706 due nine months after death with a six-month extension; state estate taxes may apply separately with lower exemptions. This is a planning estimate, not tax advice.
Sources: IRS estate and gift tax guidance and Form 706 instructions; figures reflect published federal exemption amounts. This calculator is for planning only — estate tax rules change often and individual situations vary, so consult a qualified tax professional. Last reviewed October 2026.
Estimate federal estate tax from gross estate, debts and the exemption — see the taxable amount and tax due.
Enter the gross estate value, subtract debts and expenses, then subtract the federal exemption amount. The calculator applies the flat 40% federal rate to whatever remains above the exemption.
Formula: Taxable estate = gross − debts − exemption; tax = taxable × 40%. Example: $15M gross − $1M debts − $13.61M exemption = $390,000 taxable → $156,000 tax.
A flat 40% on the amount above the exemption. With a $15M estate, $1M in debts and the $13.61M exemption, the tax is about $156,000.
The amount that passes tax-free — $13.61M per person in 2024. It is adjusted yearly, so confirm the current figure before planning.
Only estates above the exemption — the vast majority of estates owe nothing. State-level estate or inheritance taxes may still apply at lower thresholds.
Lifetime gifts, trusts, charitable giving and proper exemption use (including portability for couples) all shrink the taxable estate — work with an estate attorney.
No — it is a planning estimate only. Estate law changes often and individual situations vary; consult a tax professional.
Also try our Investment Calculator — or browse all Financial Calculators.