What Is the Estate Tax in Washington State?

The Washington state estate tax is a tax on the transfer of wealth at death, charged against the estate of anyone who was a Washington resident or who owned real estate or tangible personal property in the state. For 2026 deaths, the tax applies only to estates valued at $3,076,000 or more, with graduated rates running from 10% up to 35% on the amount above that threshold.¹² Because the state threshold sits far below the federal exemption, many families owe Washington tax even when they owe nothing to the IRS.

Who Has to Pay

The tax falls on the estate itself, not on the people who inherit. That makes it different from an inheritance tax: beneficiaries don’t get a bill. The executor or personal representative files the return and pays the tax from estate assets before distributing anything to heirs.

Washington residents are taxed on everything they owned at death, wherever that property happens to sit. Non-residents are taxed only on real estate and tangible personal property physically located in Washington.² For a resident whose estate includes out-of-state property, the tax is first calculated as if everything were in Washington and then apportioned to reflect only the Washington share.³ Stocks, bonds, and bank accounts owned by a resident are treated as Washington property no matter where the brokerage or bank is located.

The 2026 Exclusion Amount

For deaths in 2026, the applicable exclusion is $3,076,000.¹ An estate with a gross value below that figure owes nothing and doesn’t need to file a return. Only the portion of the estate above $3,076,000 is subject to tax.

This figure went up substantially in mid-2025. From 2018 through June 30, 2025, the exclusion was $2,193,000. Starting July 1, 2025, the base rose to $3,000,000, and from 2026 forward it adjusts each year for inflation using the Seattle-area consumer price index.⁴ The annual adjustment can only hold the exclusion steady or raise it; it can’t drop.

2026 Tax Rates

Washington uses a graduated rate schedule. The brackets apply to the taxable estate, which is the amount left after subtracting the exclusion and allowable deductions. For deaths on or after July 1, 2025, the rates are:¹

$0 to $1,000,000: 10%
$1,000,000 to $2,000,000: 15%
$2,000,000 to $3,000,000: 17%
$3,000,000 to $4,000,000: 19%
$4,000,000 to $6,000,000: 23%
$6,000,000 to $7,000,000: 26%
$7,000,000 to $9,000,000: 30%
$9,000,000 and above: 35%

Take an estate with a gross value of $5,000,000 and no deductions beyond the exclusion. The taxable amount is $1,924,000. The first $1,000,000 is taxed at 10% for $100,000, and the remaining $924,000 is taxed at 15% for $138,600. Total tax: $238,600.²

The 35% top bracket is new. Before July 1, 2025, the maximum rate was 20%, so estates above roughly $9 million in taxable value now face nearly double the top rate they would have paid a year earlier.

What Counts in the Gross Estate

The gross estate starts with the fair market value, as of the date of death, of everything the decedent owned or had an interest in. A few categories trip people up.

Community Property

Washington is a community property state. For a married decedent, the full value of community property is reported on the return, but only the decedent’s half is included in the taxable estate; the surviving spouse’s half is subtracted out.⁵ Separate property of the decedent is included in full. Getting the community-versus-separate split right matters, because a mistake can swing the taxable estate by hundreds of thousands of dollars.

Life Insurance

Life insurance proceeds are part of the gross estate if the policy was on the decedent’s life or owned by the decedent, even when the money is paid directly to a named beneficiary.⁵ What matters is whether the decedent held any ownership rights in the policy. Transferring a policy to someone else within three years of death doesn’t take it out of the estate; the proceeds are added back in.

Lifetime Gifts

Washington has no separate gift tax. Outright gifts made during life generally stay outside the Washington gross estate.⁵ The exceptions involve transfers made within three years of death where the decedent kept a life interest or the power to revoke the transfer, transfers of life insurance, and federal gift tax paid within three years of death. Older gifts, and clean gifts without retained strings, remain outside the estate.

Deductions That Cut the Tax

Allowable deductions come off the gross estate alongside debts, funeral costs, and administrative expenses.

Marital Deduction

Property passing to a surviving spouse or state-registered domestic partner qualifies for an unlimited marital deduction, which can wipe out the tax entirely on the first death.⁶ If the surviving spouse isn’t a U.S. citizen, the property has to pass through a qualified domestic trust (QDOT) to qualify.⁵

One difference from federal law matters a lot for planning. Washington does not allow portability of the unused exclusion between spouses.⁵ Federally, a surviving spouse can inherit the deceased spouse’s unused exemption. In Washington, each estate gets its own $3,076,000 exclusion and nothing more. A couple that leaves everything outright to the survivor often wastes the first spouse’s exclusion, producing a bigger tax bill at the second death. Trust-based structures, including a QTIP election on the Washington return, exist to preserve both exclusions.⁶

Farm Property

Qualifying farm real estate and tangible farm personal property can be deducted from the gross estate.⁷ The decedent or a family member must have used the property for farming, and the estate has to meet ownership and use requirements tied to federal provisions.

Family-Owned Business

A qualified family-owned business interest can be deducted if the business makes up more than 50% of the taxable estate before the exclusion is applied. The decedent or family members must have owned the business and been actively involved in it for at least five of the eight years before death.⁸

Filing and Paying

A Washington estate tax return is required whenever the gross estate equals or exceeds the applicable exclusion. Both the return and payment are due nine months after the date of death.⁹

The executor compiles an inventory of assets at date-of-death fair market value. Real estate, closely held businesses, and other hard-to-value assets usually need professional appraisals. If a federal Form 706 is also filed, a complete copy, including every schedule, has to accompany the Washington return.¹⁰ Returns go to the Department of Revenue at PO Box 47474, Olympia, WA 98504-7474.¹¹

Extensions

If you’ve obtained a federal extension on Form 4768, send a copy to the Department of Revenue; Washington grants the same extension automatically.⁹ File that copy by the original Washington due date or within 30 days of issuance, whichever is later. Estates with no federal filing requirement can request a state-only extension on the Department’s form.¹² An extension of time to file is not an extension of time to pay. Interest keeps running on any unpaid balance from the original nine-month deadline.

Penalties and Interest

Late filing costs 5% of the tax due for each month the return is overdue, capped at the lesser of 25% of the tax or $1,500.¹³ Interest on unpaid tax runs from the original nine-month due date to the date of payment, even during an approved extension. For 2026, the annual rate is 6%.¹ Submitting an estimated payment with the extension request keeps the interest tab down.

How This Differs From the Federal Estate Tax

Owing no federal estate tax does not mean owing no Washington tax. For 2026, the federal basic exclusion is $15,000,000 per person, and a federal Form 706 is required only when the gross estate exceeds that amount.¹⁴¹⁵ A $5,000,000 Washington estate owes nothing to the IRS but can still owe the state six figures. Estates large enough to clear the federal threshold face both taxes, though the federal return allows a deduction for state estate taxes paid.

1
Washington Department of Revenue. Estate Tax Tables
2
Washington State Legislature. Washington Code 83.100.040 – Estate Tax Imposed—Amount of Tax
3
Washington Department of Revenue. Estate Tax Apportionment for Out of State Property
4
Washington State Legislature. Washington Code 83.100.020 – Definitions
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Washington Department of Revenue. Estate Tax FAQ
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Washington State Legislature. Washington Code 83.100.047 – Marital Deduction, Qualified Domestic Trust—Election
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Washington State Legislature. Washington Code 83.100.046 – Deduction—Property Used for Farming—Requirements, Conditions
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Washington State Legislature. Washington Code 83.100.048 – Deduction—Qualified Family-Owned Business Interests
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Washington State Legislature. Washington Code 83.100.050 – Tax Returns—Filing Dates—Extensions
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Washington State Department of Revenue. Estate Tax Filing Instructions With Checklist
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Washington Department of Revenue. Estate Tax
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Washington Department of Revenue. Estate Tax Filing Options and Forms
13
Washington State Legislature. WAC 458-57-135 – Washington Estate Tax Return to Be Filed—Penalty
14
Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
15
Internal Revenue Service. Estate Tax