The filing important date depends on when the person died

An estate tax return (Form 706) is due nine months after the date of death. If the person died on March 15, the return is due December 15 of the same year. The executor or personal representative files this return with the IRS, not the beneficiaries.

The nine-month important date is firm for most estates. However, the executor can request an automatic six-month extension by filing Form 4768 before the original important date. This moves the due date to fifteen months after death. Extensions are common and do not require the IRS to approve a reason — you straightforward file the form on time.

If the estate does not owe federal estate tax, a return may not be required at all. The threshold changes yearly. In 2024, for example, estates under $13.61 million do not owe tax and typically do not file Form 706. Your state may have its own lower threshold and its own return requirement, even if the federal return is not due.

Key Takeaways

  • Form 706 is due nine months after death, with an automatic six-month extension available if filed before the original important date.
  • Estates below the federal threshold (which varies by year) usually do not owe tax and do not file a federal return, but state returns may still be required.
  • The executor or personal representative is responsible for filing, not the heirs or beneficiaries.
  • Missing the important date without an extension can result in penalties and interest, even if no tax is ultimately owed.
  • Some estates file Form 706 even when no tax is due, to start the statute of limitations clock and protect beneficiaries from future IRS challenges.

When an estate does not need to file

Most estates do not file Form 706 because they fall below the federal estate tax threshold. In 2024, that threshold is $13.61 million per person. An estate worth less than that amount owes no federal estate tax and has no federal filing requirement.

However, state estate tax and inheritance tax rules vary widely. Some states have their own thresholds, which are often much lower than the federal amount. New York, for example, has a state estate tax threshold of $6.94 million in 2024. Massachusetts taxes estates over $1 million. If the estate is subject to state tax, a state return may be due even if the federal return is not.

The executor should check both the federal threshold for the year of death and the state threshold where the deceased lived or owned property. A tax professional or the state's department of revenue can confirm whether a return is required.

Why some estates file even when no tax is owed

Some executors file Form 706 voluntarily, even though the estate is below the threshold and owes no tax. This is a strategic choice, not a requirement. The main reason is to start the statute of limitations for IRS review.

When you file Form 706, the IRS generally has three years to challenge the values you reported on the return. If you do not file, the IRS can challenge the estate's value indefinitely. For large estates close to the threshold, or estates with assets that are hard to value (like closely held businesses or art), filing the return locks in the values and protects beneficiaries from surprise audits years later.

This strategy is most useful when the estate is near the threshold, when asset values are uncertain, or when the executor wants to claim a portability election (which allows an unused exemption to pass to the surviving spouse). A tax professional can advise whether filing makes sense in your situation.

What happens if you miss the important date

If Form 706 is due and not filed by the important date — and no extension was requested — the IRS can assess penalties. The penalty is typically 5% per month of the unpaid tax, up to 25% of the total. Interest also accrues on any unpaid tax from the original due date.

Even if the estate ultimately owes no tax, filing late can trigger penalties and interest calculations. The executor can request relief by filing Form 2688 (process for Extension of Time to File) after the important date, but relief is not automatic and requires showing reasonable cause for the delay.

If the estate does owe tax and the return is filed very late, the penalties and interest can be substantial. This is one reason to file an extension on time if you are unsure whether you will meet the nine-month important date.

How to request an extension

To extend the filing important date, the executor files Form 4768 (process for Extension of Time to File U.S. Individual Income Tax Return) with the IRS. Despite its name, Form 4768 is also used for estate tax returns. The form must be filed before the original nine-month important date.

Filing Form 4768 automatically grants a six-month extension. You do not need to explain why you need more time or wait for approval. The new important date becomes fifteen months after death. If you need more time after that, you can request a second extension, though the IRS is less likely to grant it.

The extension gives you time to gather asset values, obtain appraisals, and prepare the return. It does not extend the time to pay any tax owed — if tax is due, it is technically due on the original nine-month date, though the IRS typically does not enforce payment until the return is filed.

State estate and inheritance tax important date

States with their own estate or inheritance taxes set their own important date, which often mirror the federal nine-month rule but sometimes differ. Some states require the return within nine months of death; others allow a different timeframe. A few states tie their important date to when the federal return is filed.

The executor should contact the state's department of revenue or a tax professional to confirm the state important date and whether an extension is available. Missing a state important date can result in state penalties and interest, separate from any federal consequences.

If the estate owns property in multiple states, returns may be due in more than one state. The executor's job includes tracking all of these important date and filing on time or requesting extensions in each jurisdiction where required.

Working with a tax professional

Preparing Form 706 is complex. It requires valuing all estate assets as of the date of death, calculating deductions, and understanding portability elections and other tax strategies. Most executors work with a tax professional or estate attorney to prepare and file the return.

A tax professional can also advise whether filing is necessary, whether an extension makes sense, and whether filing voluntarily (even when not required) would protect the beneficiaries. They can may support the return is filed correctly and on time, avoiding penalties and interest.

The cost of professional help is typically paid from the estate's assets, not by the executor personally. This is a reasonable expense of estate administration.

Frequently Asked Questions

What if the person died on the last day of a month — is the return due on the last day of a month nine months later?

Yes. If death occurred on January 31, the return is due April 30 (nine months later). If death occurred on a date that does not exist in the ninth month (like January 31 in a year where February has 28 days), the return is due on the last day of that month.

Can the executor file the return late without requesting an extension first?

Technically yes, but it is not recommended. Filing late without an extension triggers automatic penalties and interest. The executor can request relief by filing Form 2688 after the important date, but relief requires showing reasonable cause and is not may provide. Filing an extension on time is the safer approach.

If the estate is below the threshold and no return is required, do beneficiaries still have to report inherited assets on their tax returns?

No. Inherited assets are not taxable income to the beneficiary, regardless of the estate's size. Beneficiaries do not report the inheritance itself on their personal tax returns. However, income earned by the estate after death may be taxable to beneficiaries or the estate, depending on the situation.

Does the executor have to pay the estate tax before filing the return?

No. The return is filed first, and payment is due with the return (or by the original nine-month important date if an extension is filed). The IRS will bill the estate for any tax owed. However, if the estate does not have enough liquid assets to pay the tax by the important date, the executor can request a payment plan or installment agreement.

What if the estate is still being settled after nine months — can the return be delayed?

The return important date is separate from when the estate is fully settled. The executor can file the return on time (or request an extension) even if the estate is still being administered. If final distributions to beneficiaries are delayed, the executor can file an amended return later if needed.