When Your Estate Tax Return Is Due and What Deadline You're Working With

The Estate Tax Return important date

The federal estate tax return, called Form 706, is due nine months after the person's death. That nine-month window is the standard important date set by the IRS, and it applies whether the estate owes taxes or not. If the estate is large enough to require filing, you cannot skip the return just because you think no tax is owed—the IRS decides that, not you.

The nine months starts from the date of death, not from when you discover the estate or when probate begins. If someone died on March 15, the return is due December 15 of the same year. Mark that date clearly, because missing it without an extension creates penalties that compound quickly.

You can request a six-month extension before the original important date expires. This pushes the due date to fifteen months after death. The extension is not automatic—you must file Form 4768 with the IRS before the nine-month important date passes. Many estates file for this extension as routine practice, straightforward to have more time to gather documents and value assets.

Key Takeaways

Form 706 is due nine months after the person's death, regardless of whether the estate owes federal tax.
A six-month extension moves the important date to fifteen months after death, but you must request it on Form 4768 before the original nine-month important date.
State estate tax returns, if required, follow different important date that vary by state and may be shorter than the federal important date.
The executor or administrator is responsible for filing, and penalties for late filing include interest on any tax owed plus a failure-to-file penalty.
Even estates below the federal filing threshold may need to file to claim certain deductions or to satisfy state requirements.

Who Files the Return and When to Start

The executor (or administrator, if there is no will) is responsible for filing Form 706. This person should begin gathering documents when ready after death: the will, deeds to real property, bank and investment statements, life insurance policies, and any business interests. Valuing these assets takes time, especially if the estate includes real estate, a business, or significant investments.

You do not have to wait for probate to finish before filing the return. In fact, many executors file the return while probate is still open, because the nine-month important date does not pause for court proceedings. If you are unsure whether the estate is large enough to require filing, a tax professional can review the assets and advise you. The federal threshold changes yearly—in 2024 it is $13.61 million per person—but state thresholds are often much lower.

State Estate Tax important date

Fifteen states plus Washington, D.C., impose their own estate taxes, and their important date are not always the same as the federal important date. Some states require the return within nine months of death, matching the federal rule. Others set a shorter window—some as brief as four or five months. A few states tie their important date to the federal return, meaning if you file Form 706, you have automatically met the state important date.

The state where the person lived at death is the one that matters most, though if the estate owns real property in another state, that state may also require a return. Check with the state tax authority or a local tax professional to confirm the exact important date. Missing a state important date can trigger penalties separate from any federal penalties, and some states charge interest from the date of death rather than from the due date.

What Happens If You Miss the important date

The IRS charges a failure-to-file penalty if Form 706 is late and tax is owed. The penalty is 5 percent of the unpaid tax for each month the return is late, up to a maximum of 25 percent. On top of that, interest accrues on any unpaid tax from the date of death until the date you pay. These charges add up quickly on large estates.

If you file late but no tax is owed, the penalty may be waived if you can show reasonable cause—for example, the executor was ill, or critical documents were lost. The IRS is more forgiving when no tax is due, but you still need to request the waiver and explain the delay. Filing the return, even late, is always better than not filing at all, because the IRS will eventually discover the estate and assess penalties based on their own valuation of assets.

Requesting an Extension

File Form 4768 (process for Extension of Time to File U.S. Individual Income Tax Return) before the nine-month important date to request six more months. You can file this form on paper or electronically through the IRS e-file system. The extension is usually granted without question if you file the form on time, even if you do not have a detailed reason.

An extension gives you until fifteen months after death to file the return, but it does not extend the time to pay any tax owed. If the estate will owe tax, you should estimate the amount and pay it by the original nine-month important date to avoid interest charges. You can adjust the payment when you file the actual return if your estimate was too high or too low.

Valuing Assets for the Return

Form 706 requires you to list every asset the person owned and assign it a value as of the date of death. This is called the stepped-up basis, and it is the value used for both estate tax and income tax purposes. For stocks and bonds, the value is the closing price on the date of death. For real estate, you typically need a professional appraisal. For a business, you may need a business valuation informed.

Some assets are straightforward—bank accounts show their balance on the date of death. Others are harder to pin down. If you are unsure how to value something, a tax professional or appraiser can help. The IRS may challenge your valuations if they seem too low, so document how you arrived at each figure. Keep receipts, appraisals, and statements in a file with the return.

When the Estate Is Below the Filing Threshold

If the total value of the estate is below the federal threshold for the year of death, you may not be required to file Form 706. However, you should still check whether a state return is required, because state thresholds are often lower. Some states require a return for estates as small as $1 million.

Even if no return is required, filing one may be worth doing anyway. Filing Form 706 creates an official record of the asset values, which can protect heirs from IRS challenges later. It also allows the estate to claim certain deductions and credits that reduce income tax owed by the estate or by heirs. A tax professional can advise whether filing makes sense in your situation.

Frequently Asked Questions

Can I file Form 706 before the person dies?

No. The return covers the person's final tax year and the value of assets on the date of death. You cannot file it until after death occurs. However, you can begin gathering documents and organizing information while the person is still alive, which speeds up the process later.

What if the executor lives in a different state than the person who died?

The location of the executor does not matter. The important date is the same nine months from the date of death, and the return is filed with the IRS regardless of where the executor lives. However, if the estate owns real property in another state, that state may require its own return with its own important date.

Do I need a tax professional to file Form 706?

Form 706 is complex, and most executors work with a tax professional or attorney to file it. The form requires detailed asset valuations and calculations that are straightforward to get wrong. A mistake can trigger an audit or penalties. If the estate is small and straightforward, you might file it yourself, but for most estates, professional help is worth the cost.

What if I discover assets after I file the return?

You can file an amended return, called Form 706-A, to add assets you missed. There is no penalty for amending if you file it within a reasonable time. If the amended return shows additional tax owed, you will owe interest from the original due date, but not a failure-to-file penalty.

Does the extension give me more time to pay the tax?

No. The extension extends the filing important date to fifteen months after death, but any tax owed is still due nine months after death. If you cannot pay by then, you can request a payment plan from the IRS, but interest will accrue on the unpaid balance.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.