Updated October 16, 2026. Quick answer: Form 706 is the federal estate and generation-skipping transfer tax return that the executor files. The instructions say it is due within 9 months after the date of the decedent’s death, and Form 4768 gives an automatic 6-month extension of time to file. The extension to file is not an extension to pay, which is a separate request.
Form 709 (gift tax return), read line by line: Form 709 Part I lines 1 to 21, Form 709 Part II lines 1 to 12, Form 709 Part II lines 13 to 20 and Form 709 Schedule D.
Form 706 (estate tax return), read line by line: Form 706 Part III elections, Form 706 Parts IV and V, Form 706 Part VI portability and Form 706 Schedule A real estate.
More IRS forms and schedules, read line by line: Form 7004 instructions.
Quick reference
| Item | Figure printed in the instructions |
|---|---|
| Due date | 9 months after the date of death |
| Automatic extension to file (Form 4768) | 6 months |
| Gross estate plus adjusted taxable gifts and specific exemption, decedents dying in 2026 | more than $15,000,000 |
When Form 706 is due
The Form 706 instructions state the rule in the When To File section: “You must file Form 706 to report estate and/or GST tax within 9 months after the date of the decedent’s death.” The Form 4768 instructions repeat it with a rule for short months: “The due date for Form 706 and Form 706-NA is 9 months after the date of the decedent’s death.” “If there is no numerically corresponding date in the 9th month, the due date is the last date of the 9th month.”
The same section covers the weekend: “If the due date falls on a Saturday, Sunday, or legal holiday, the return is due on the next business day.”
| Item | As printed |
|---|---|
| Due date | “You must file Form 706 to report estate and/or GST tax within 9 months after the date of the decedent’s death.” |
| No matching date | “If there is no numerically corresponding date in the 9th month, the due date is the last date of the 9th month.” |
| Weekend or holiday | “If the due date falls on a Saturday, Sunday, or legal holiday, the return is due on the next business day.” |
| Automatic extension | “the automatic extension of time to file is 6 months from the original due date of the applicable return.” |
A longer treatment of how this deadline fits with the other post-death dates is on the estate tax return deadline page. The gift tax return has its own dates, covered on the Form 709 due date page.
Example dates
These three dates of death are illustrations, not IRS examples. Each nine month date is computed here by adding 9 months to the date of death, and each six month date by adding 6 months to the nine month date. All six dates fall on weekdays, so the weekend rule quoted above moves none of them. The weekdays come from a calendar calculation, and none of these dates is published by the IRS.
| Date of death (illustration, not an IRS example) | Nine months after, computed here | Six months further, computed here |
|---|---|---|
| January 20, 2026 (Tuesday) | October 20, 2026 (Tuesday) | April 20, 2027 (Tuesday) |
| March 3, 2026 (Tuesday) | December 3, 2026 (Thursday) | June 3, 2027 (Thursday) |
| August 12, 2026 (Wednesday) | May 12, 2027 (Wednesday) | November 12, 2027 (Friday) |
The automatic 6 month extension on Form 4768
The Form 706 instructions point to the extension form: “If you are unable to file Form 706 by the due date, you may receive an extension of time to file.” “Use Form 4768, Application for Extension of Time To File a Return and/or Pay U.S. Estate (and Generation-Skipping Transfer) Taxes, to apply for an automatic 6-month extension of time to file.”
The Form 4768 instructions explain the timing: “If you are applying for an automatic 6-month extension of time to file Form 706, 706-A, 706-NA, or 706-QDT, file Form 4768 by the original due date for the applicable return.” “You don’t have to explain why you are asking for an automatic extension.”
There is no routine confirmation to wait for: “We will only contact you if your request for extension of time to file is denied.” A request that missed the automatic deadline has a separate route: “an extension of time to file may still be granted if good cause is shown.”
An extension to file is not an extension to pay
The Form 4768 instructions put the warning first in Part II: “An extension of time to file doesn’t extend the time to pay.”
The Form 706 instructions give the payment date: “The estate and GST taxes are due within 9 months of the date of the decedent’s death. You may request an extension of time for payment by filing Form 4768.”
The payment extension has its own filing mechanics: “A separate Form 4768 is required to request an extension of time to pay” and “When requesting an extension of time to pay, don’t send Form 4768 with Form 706.” “An application for an extension of time to pay estate tax applied for after the estate tax due date will generally not be considered by the IRS.”
Interest is charged either way: “Interest must be paid on any estate and GST taxes that aren’t paid in full by the original due date of the tax return, regardless of whether an extension of time to file and/or pay has been obtained.”
Portability and the filing threshold
Who has to file at all depends on the size of the estate. For decedents who died in 2026 the instructions say Form 706 “must be filed by the executor of the estate of every U.S. citizen or resident:” “Whose gross estate, plus adjusted taxable gifts and specific exemption, is more than $15,000,000; or” “Whose executor elects to transfer the deceased spousal unused exclusion (DSUE) amount to the surviving spouse, regardless of the size of the decedent’s gross estate.”
The portability election is tied to the deadline: “An executor can only elect to transfer the DSUE amount to the surviving spouse if the Form 706 is filed timely, that is, within 9 months of the decedent’s date of death or, if you have received an extension of time to file, before the 6-month extension period ends.”
A timely return is defined again in the portability section: “A timely filed return is one that is filed on or before the due date of the return, including extensions.” For an estate that was not otherwise required to file, a later route exists: “Executors filing to elect portability may now file Form 706 on or before the fifth anniversary of the decedent’s death.” The statement and the conditions are in the instructions.
Late filing penalty
The penalty is set in section 6651, and the instructions describe it this way: “Section 6651 provides for penalties for both late filing and late payment unless there is reasonable cause for the delay.” “The late filing penalty will not be imposed if the taxpayer can show that the failure to file a timely return is due to reasonable cause.”
Both forms point to the extended period too. The Form 4768 instructions say “Penalties may be imposed for failure to file the estate (and GST) tax return within the extension period granted, or failure to pay the balance of the estate (and GST) tax due within the extension period granted.”
When a penalty notice arrives, the instructions say “Do not attach an explanation when you file Form 706.” “If you receive a notice about penalties after you file Form 706, send an explanation and we will determine if you meet reasonable-cause criteria.”
The edition read for this page is the Instructions for Form 706 (Rev. July 2026) and the Instructions for Form 4768 (Rev. February 2020), which are the revisions irs.gov served when they were read on 2026-10-16. The example dates above are computed here for illustration and are not published by the IRS. Check the revision printed on the form you are filing, because a later revision can change the dates and the dollar thresholds.
Common mistakes
- Assuming the 6 month extension also extends payment. The Form 4768 instructions say an extension of time to file doesn’t extend the time to pay, and the Form 706 instructions say the tax is due within 9 months of death unless a payment extension is requested.
- Missing the Form 4768 deadline. The instructions require the automatic extension request by the original due date, and a portability election is only valid if Form 706 is filed timely, including extensions.
- Not counting the due date correctly. The instructions use the last date of the 9th month when there is no corresponding date and move a weekend or holiday due date to the next business day.
Related: estate tax return deadline, Form 709 due date and extension, Form 706 instructions, deadlines after a death calculator, and Form 1041 due date and extension.
Sources
- Instructions for Form 706 (Rev. July 2026): https://www.irs.gov/pub/irs-pdf/i706.pdf
- Instructions for Form 4768 (Rev. February 2020): https://www.irs.gov/pub/irs-pdf/i4768.pdf
Read from the IRS documents linked above on October 16, 2026. General information, not tax advice. Your own facts decide the outcome, and a preparer, the account provider or the IRS is the right place to confirm anything consequential.