An estate tax return (Form 706) is required when the gross estate plus adjusted taxable gifts (and certain prior specific exemption amounts, if applicable) exceeds the federal filing threshold (generally the “basic exclusion amount”) for the decedent’s year of death. This filing requirement is set by Internal Revenue Code § 6018(a)(1). 

In addition, a Form 706 is commonly filed even when the estate is below the filing threshold if the estate is filing solely to elect portability (to transfer the deceased spouse’s unused exclusion amount (DSUE) to the surviving spouse). Portability is made on a timely filed Form 706. The IRS provides special reporting rules for certain marital/charitable-deduction property when filing only for portability and the estate is below the basic exclusion amount. 

Current filing thresholds (year of death):

2025 deaths: $13,990,000

2026 deaths: $15,000,000

Federal (IRS) — Form 706-NA (Nonresident Not a Citizen of the United States)

For a nonresident not a U.S. citizen (NRNC) decedent, the executor must file Form 706-NA if the date-of-death value of U.S.-situated assets, together with the decedent’s adjusted taxable gifts and certain historical gift tax exemption concepts described by the IRS, exceeds $60,000 (this threshold is not indexed for inflation). 

Due Date (Federal)

Form 706 is generally due 9 months after the decedent’s date of death. An automatic 6-month extension to file is available by filing Form 4768 on or before the due date. 

State Law Note 

Separate from the federal estate tax return, state estate tax and inheritance tax filing requirements are administered at the state level (and sometimes locally). If a state filing is required, the controlling authority is the applicable state revenue department/tax agency (and/or the agency administering estate/inheritance tax in that state). 

Still got questions and concerns? Speak to our tax specialists and let them assist you.

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