How to File a Final Tax Return for a Deceased Parent

To file a final tax return for a deceased parent, the executor, court-appointed administrator, or surviving spouse files Form 1040 (or 1040-SR) covering income your parent received from January 1 through the date of death. The return is due on the same April 15 deadline that would have applied if your parent were still alive. The final 1040 is often only part of the job: post-death income may require a separate estate return, and any tax the estate owes has to be settled before assets go to the family.

Who Signs and Files

The person with authority depends on how the estate is being handled. If a probate court has appointed an executor under a will, or an administrator when there is no will, that person files. When no court appointment has been made, a surviving spouse can file a joint return, or another family member can step in as the personal representative.

Whoever takes the role should file IRS Form 56 to notify the IRS of the fiduciary relationship. This tells the IRS where to send correspondence and establishes your authority to act on the account.¹ Form 56 is not required in every situation, but skipping it creates friction if you later need to resolve a balance, request a transcript, or claim a refund.

If your parent’s estate qualifies for your state’s simplified small-estate procedure, you can still file the tax return without a formal probate appointment. Every state sets its own threshold, so check your local probate court if you’re not sure.

What to Gather Before You Start

Certified death certificate. You will need several copies for banks, brokerages, and the IRS.
The decedent’s Social Security number for the final 1040. The estate itself will need a separate EIN if it earns income.
Income documents through the date of death: W-2s, 1099s for interest, dividends, and retirement distributions, and Form SSA-1099 for Social Security.
Prior-year returns to identify recurring income and carryforward items like capital losses. If you don’t have copies, submit Form 4506-T with a death certificate and proof of authority to request free transcripts.²
Proof of authority: Letters Testamentary, Letters of Administration, or a completed Form 56.

Check whether your parent filed returns for prior years. If they hadn’t, the personal representative may be required to file those too.³ Penalties and interest on old balances become the estate’s problem.

The Deadline Is Still April 15

The final Form 1040 is due on the normal April 15 deadline of the year after death.⁴ If your parent died on March 3, 2025, the final 2025 return is due April 15, 2026. If your parent died in January 2026 before filing their 2025 return, you owe two returns: the 2025 return by April 15, 2026, and the 2026 final return by April 15, 2027.

An automatic six-month extension is available by filing Form 4868 before April 15. The extension pushes back only the filing date, not the payment date. If you expect a balance due, estimate and pay it by April 15 to avoid interest and late-payment penalties.⁴

Filing Status

Filing status is based on your parent’s situation as of the date of death, the same status they would have used had they lived the whole year.⁵

A surviving spouse who doesn’t remarry during the year of death can file a joint return that includes the surviving spouse’s income for the full year and the decedent’s income through the date of death.⁵ When both a court-appointed representative and a surviving spouse are involved, both must sign. A joint return generally produces a lower tax bill than filing separately. If the surviving spouse remarries before December 31 of the year of death, a joint return with the decedent is not allowed.

For the two tax years after the year of death, a surviving spouse may qualify for Qualifying Surviving Spouse status, which uses the same brackets as married filing jointly. Qualification requires not remarrying, having a dependent child living in the home, and paying more than half the cost of maintaining that household.⁶

What Income Belongs on the Final Return

The final 1040 includes only income your parent actually received (or constructively received) before the date of death.³ For a cash-basis individual, that means wages paid before death, interest posted before death, and dividends received before death.

Income earned but not yet received at death is Income in Respect of a Decedent, or IRD. IRD does not belong on the final 1040. It is taxed to whoever ultimately receives it, either the estate or a named beneficiary.⁵ Common IRD includes a final paycheck issued after death, IRA and 401(k) distributions passing to beneficiaries, accrued U.S. Savings Bond interest that was never reported annually, and remaining partnership payments owed to the decedent.

When a bank or brokerage issues a 1099-INT or 1099-DIV for the full year under either the decedent’s SSN or the estate’s EIN, split the income between the final 1040 and the estate’s Form 1041 based on the date of death. Report on each return only the amount received during the period that return covers, and attach a note explaining the allocation.

Deductions

Claim the full standard deduction on the final return without prorating it for the partial year. For 2026, the standard deduction is $16,100 for single filers and $32,200 for married filing jointly.⁷ An additional standard deduction amount applies if your parent was 65 or older or blind. You can itemize instead if that produces a better result, and all deduction rules follow those for a living taxpayer.

Medical Expenses Paid After Death

Expenses your parent paid before death are deductible on the final return, subject to the 7.5% of AGI floor, if you itemize. Medical expenses paid by the estate within one year after the date of death can also be treated as if the decedent paid them, which lets you deduct them on the final 1040 instead of on the federal estate tax return.⁵

To make this election, attach a statement to the return declaring that the expenses have not been and will not be claimed on Form 706. It’s either/or; you cannot deduct the same expenses on both returns.⁸ For medical bills incurred in a year before death, file Form 1040-X for that earlier year to claim them. Amounts that fall below the 7.5% AGI threshold and can’t be deducted on the income tax return also can’t be shifted to the estate tax return.

Signing, Marking, and Submitting the Return

On a paper return, write “DECEASED,” the decedent’s name, and the date of death across the top of the first page.⁹ How you sign depends on your situation.

A court-appointed representative filing alone signs the return, writes their title (executor, administrator, or personal representative) next to the signature, and attaches Letters Testamentary or Letters of Administration.
A surviving spouse filing a joint return with no court-appointed representative signs the return and writes “Filing as surviving spouse” in the signature area for the decedent.
When both a court-appointed representative and a surviving spouse are filing jointly, both must sign.

Claiming a Refund

If the final return shows a refund, you may need to attach Form 1310. Not always: a surviving spouse filing a joint return does not need Form 1310, and neither does a court-appointed representative filing an original return with the court certificate attached.¹⁰ You do need Form 1310 if you are neither a surviving spouse nor a court-appointed representative, for example an adult child handling affairs without a formal appointment.

E-filing is available through most tax software. Paper filing is often more practical when you need to attach Letters Testamentary or Form 1310, since electronic filing doesn’t always accommodate those attachments smoothly. Mail paper returns to the IRS service center for the decedent’s last address.

When the Estate Itself Owes a Return

After death, the estate is its own taxable entity. Income generated after the date of death, such as bank interest, rental income, and dividends, belongs to the estate rather than to your parent. If the estate earns $600 or more in gross income during a tax year, or has a beneficiary who is a nonresident alien, it must file Form 1041.¹¹

Before filing Form 1041, get an EIN for the estate. Apply online at IRS.gov/EIN and receive the number immediately.¹² Enter the decedent’s name followed by “Estate” as the entity name, and list the executor or administrator as the responsible party.¹³

Estates can pick a fiscal year instead of a calendar year. The estate’s first tax year can be any period of up to 12 months ending on the last day of a month.¹¹ If your parent died in March 2026, a fiscal year ending in September would push the estate’s first filing deadline to January 15, 2027, which is the 15th day of the fourth month after the fiscal year closes.

Estate income tax brackets are sharply compressed compared to individual brackets. For 2026, the estate reaches the 37% top rate at just $16,000 of taxable income. Income distributed to beneficiaries is taxed on their personal returns at their own rates instead. The estate takes a deduction for what it distributes, and each beneficiary gets a Schedule K-1 (Form 1041).¹¹ Because the estate brackets are so tight, distributing income often saves real money.

Stepped-Up Basis on Anything You Inherit

When you inherit property from a deceased parent, the tax basis resets to fair market value on the date of death.¹⁴ If your parent bought a house for $80,000 and it was worth $350,000 at death, your basis is $350,000. Sell for $355,000 and you owe capital gains on $5,000, not $275,000. The step-up applies to stocks, real estate, and other capital assets.

If the executor files a federal estate tax return and elects alternate valuation, the basis becomes the value six months after death (or the date of sale if the asset is sold within those six months). Alternate valuation is only available when it would decrease both the gross estate value and the total estate tax.¹⁵ Keep appraisals, brokerage statements from the date of death, and county property assessments; the IRS can challenge a claimed basis with no documentation behind it.

Federal Estate Tax and Portability

Most estates owe no federal estate tax. For deaths in 2026, the exemption is $15,000,000 per person, so only estates above that threshold owe federal estate tax.¹⁶ Estates over the threshold must file Form 706 within nine months of death, with an automatic six-month extension available on Form 4768.¹⁷

Even for estates well below $15,000,000, Form 706 may be worth filing if your parent had a surviving spouse. Portability lets the surviving spouse inherit any unused portion of the decedent’s exemption. Make the election by filing a complete Form 706 within nine months (or 15 with the extension). A late portability election can be filed up to five years after death under Rev. Proc. 2022-32, with “Filed Pursuant to Rev. Proc. 2022-32 to Elect Portability under section 2010(c)(5)(A)” written across the top of the return.¹⁸

Around 17 states and the District of Columbia impose their own estate or inheritance taxes, often with much lower thresholds. An estate can owe state-level tax even when it owes nothing federally.

Penalties, and Your Personal Exposure

The IRS doesn’t waive penalties because the taxpayer died. Late filing costs 5% of the unpaid tax per month, up to 25%. For returns more than 60 days late, the minimum penalty is the lesser of $525 or 100% of the tax owed. Late payment adds 0.5% of the unpaid balance per month, also capped at 25%.¹⁹ Those penalties come out of estate assets and reduce what beneficiaries receive.

The part most first-time executors miss: personal liability. A fiduciary who distributes estate assets to beneficiaries before paying the decedent’s tax debts can be held personally liable for those unpaid taxes.²⁰ Don’t distribute everything to the family until you’ve confirmed all tax liabilities are settled, or set aside enough to cover them. Requesting a prompt assessment from the IRS shortens the assessment period to 18 months and helps confirm whether a balance exists before you close out the estate.

Don’t Forget the State Return

If your parent lived in a state with income tax, you’ll likely need to file a final state return covering income through the date of death. Forms, deadlines, and extension rules vary. Some states honor the federal extension automatically; others require a separate state form. Check with the tax authority in the state where your parent was a resident at death, because this step is easy to miss when the federal filing takes all your attention.

1
Internal Revenue Service. Instructions for Form 56 (12/2024)
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Internal Revenue Service. Request Deceased Person’s Information
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Internal Revenue Service. File the Final Income Tax Returns of a Deceased Person
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Internal Revenue Service. When to File
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Internal Revenue Service. Publication 559 (2025), Survivors, Executors, and Administrators
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Internal Revenue Service. Qualifying Surviving Spouse Filing Status
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Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
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Internal Revenue Service. Instructions for Form 706 (Rev. September 2025)
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Internal Revenue Service. Filing a Final Federal Tax Return for Someone Who Has Died
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Internal Revenue Service. Form 1310 (Rev. December 2025) Statement of Person Claiming Refund Due a Deceased Taxpayer
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Internal Revenue Service. Instructions for Form 1041 and Schedules A, B, G, J, and K-1 (2025)
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Internal Revenue Service. Information for Executors
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Internal Revenue Service. Instructions for Form SS-4 (12/2025)
14
Office of the Law Revision Counsel. 26 US Code 1014 – Basis of Property Acquired From a Decedent
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Office of the Law Revision Counsel. 26 US Code 2032 – Alternate Valuation
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Internal Revenue Service. What’s New – Estate and Gift Tax
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eCFR. 26 CFR 20.6081-1 – Extension of Time for Filing the Return
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Internal Revenue Service. Instructions for Form 706 United States Estate (and Generation-Skipping Transfer) Tax Return
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Internal Revenue Service. Topic No. 653, IRS Notices and Bills, Penalties and Interest Charges
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Office of the Law Revision Counsel. 26 US Code 6901 – Transferred Assets