Filing Washington Estate Tax as Personal Representative

If you've been named the personal representative of someone's estate in Washington, you may be staring at a stack of tax forms wondering where to even begin. The estate tax return isn't just paperwork mistakes can delay probate, cost the estate money, or even expose you to personal liability. Getting it right the first time protects the beneficiaries and keeps the process moving forward without unnecessary complications.

What Is a Washington Estate Tax Return?

Washington is one of a handful of states with its own estate tax. This is separate from the federal estate tax. The Washington Department of Revenue collects this tax on estates that exceed the state's exemption threshold. As of 2024, that threshold is $2.193 million.

The estate tax return filed using Form ET-21 reports the total value of the decedent's assets, applicable deductions, and the tax owed. If the gross estate exceeds the exemption, you are required to file even if you believe no tax is ultimately due after deductions.

Who Is Responsible for Filing?

The personal representative (also called an executor or administrator) is legally responsible for filing the estate tax return. This isn't optional. If you've been appointed by the court, the obligation falls on you not the beneficiaries, not the attorney, and not the accountant. While you may hire professionals to help prepare the return, the filing responsibility is yours.

You can review the full filing requirements for Washington executors to understand exactly what the state expects from you in this role.

When Does the Return Need to Be Filed?

The Washington estate tax return is due 15 months after the date of death. You can request a six-month extension using Form ET-21-EXT, but the extension to file is not an extension to pay. If tax is owed, estimated payments should still be made by the original due date to avoid interest and penalties.

Missing the deadline can trigger penalties and interest charges against the estate. Building a timeline early helps prevent this. The probate paperwork timeline for estate tax compliance lays out the key dates you'll need to track.

What Forms Do You Need to Prepare?

The primary form is the Washington State Estate Tax Return (ET-21). Depending on the estate, you may also need:

ET-21 The main estate tax return
ET-21-EXT Application for extension of time to file
ET-21-ES Estimated estate tax payment voucher
ET-21 Supplemental Schedules For itemizing assets, deductions, and credits
ET-NA A nonresident affidavit if the decedent lived outside Washington but owned property in the state

You can find all current forms on the Washington Department of Revenue's forms page. Keep in mind that the state periodically updates form versions, so always download the most current edition.

How Do You Determine the Gross Estate Value?

The gross estate includes everything the decedent owned or had an interest in at the time of death. This means:

Real property (homes, land, rental properties)
Bank accounts and cash
Investment accounts, stocks, and bonds
Retirement accounts and life insurance proceeds (in some cases)
Business interests and partnerships
Personal property like vehicles, jewelry, and art
Trusts the decedent controlled or benefited from

Assets are valued at their fair market value on the date of death not the purchase price, not the tax basis, but what the asset would sell for on the open market. For real estate, this typically means getting an appraisal. For financial accounts, you'll use the date-of-death balance.

One common mistake is forgetting to include assets that pass outside of probate, such as jointly held property or assets in a revocable living trust. Washington's estate tax applies to the gross estate, which is broader than just the probate estate.

What Deductions Can Reduce the Taxable Estate?

After calculating the gross estate, you can subtract allowable deductions. These commonly include:

Marital deduction Property passing to a surviving spouse
Charitable deduction Gifts to qualifying charities
Debts and expenses Mortgages, credit card debt, funeral costs, and administrative expenses
Family ownership deduction For qualifying family-owned businesses and farms

Properly documenting and claiming these deductions can significantly reduce or eliminate the tax owed. But you need receipts, appraisals, and records to back up every deduction claimed. The IRS equivalent concepts apply here, but Washington has its own specific rules, so don't assume federal deduction rules automatically carry over.

For a deeper look at what documents the state requires, see the guide on estate tax document obligations for executors in Washington.

Step-by-Step: How to Fill Out the ET-21

Gather all asset information. Collect statements, deeds, appraisals, and account balances as of the date of death.
Complete the asset schedules. List every asset with its fair market value. Group them by category (real property, financial accounts, personal property, etc.).
Calculate the gross estate. Add up all asset values to determine the total gross estate.
Claim applicable deductions. Subtract the marital deduction, charitable gifts, debts, and administrative expenses.
Determine the taxable estate. The gross estate minus deductions equals the taxable estate.
Apply the exemption. Washington's exemption ($2.193 million in 2024) is subtracted from the taxable estate.
Calculate the tax. Apply Washington's graduated tax rates to the amount exceeding the exemption. Rates range from 10% to 20%.
Credit for prior gifts. Report any taxable gifts made within three years of death, which Washington includes in the gross estate calculation.
Review for accuracy. Double-check every number before submitting. A wrong decimal point or missed asset can trigger an audit or delay.
File and pay. Mail the completed return with payment to the Department of Revenue. Electronic filing may also be available depending on the current year's options.

What Happens If the Estate Owes No Tax?

Even if the estate falls below the exemption threshold, you may still need to file. Washington requires a small estate affidavit in certain cases to confirm the estate's value. This isn't the same as the full ET-21, but it still requires documentation. The estate tax affidavit for executors after death walks through when and how to use it.

Filing the affidavit when appropriate clears the estate's tax obligation and allows you to proceed with distributing assets to beneficiaries without the risk of a future tax claim from the state.

Common Mistakes Personal Representatives Make

These errors come up frequently and can cost the estate time and money:

Underreporting asset values. Using outdated appraisals or guessing at values instead of getting proper assessments.
Forgetting about non-probate assets. Life insurance, retirement accounts, and jointly held property may still be taxable in Washington.
Missing the filing deadline. The 15-month window goes faster than you'd expect, especially while managing grief and other probate tasks.
Not filing when required. Some personal representatives assume that because no federal estate tax is owed, no state return is needed. Washington's exemption is much lower than the federal one.
Failing to include gifts made within three years of death. Washington pulls these back into the gross estate, which can push a borderline estate over the exemption.
Using the wrong form version. The Department of Revenue updates forms. Submitting an outdated version can cause processing delays.

Should You Hire a Professional to Help?

Many personal representatives work with a probate attorney or CPA who has experience with Washington estate tax returns. This isn't required by law, but for estates near or above the exemption threshold, professional help can prevent costly mistakes. A CPA can prepare the return, and an attorney can advise on legal obligations and potential disputes among beneficiaries.

Costs for professional help come out of the estate, not your personal funds which is an important distinction. You're not expected to pay for expert help out of pocket.

Practical Checklist Before You File

Obtain certified copies of the death certificate (you'll need several)
Get appointed as personal representative through the probate court
Inventory all assets and obtain fair market value appraisals
Collect all debt statements and expense receipts
Determine if the estate exceeds the $2.193 million exemption
Gather records of gifts made within three years of death
Download the current ET-21 form and schedules from the Department of Revenue
Calculate the tax or confirm the estate qualifies for a small estate affidavit
File the return within 15 months of the date of death
Keep copies of everything you file for your personal records

Next step: If you're in the early stages of probate, start by reading the executor paperwork timeline so you know exactly what's due and when. Building your checklist now will save you from scrambling later.