Tax Deadlines After Death in Oregon: A Master Timeline for Executors

Oregon executors often discover too late that the state's tax deadlines do not line up with the federal calendar they are following. The federal estate tax return is due nine months after death. Oregon's is twelve. The final personal income tax return has its own April 15 deadline. The fiduciary return has a third schedule based on the estate's fiscal year. Getting any one of these wrong can cost thousands of dollars in penalties and interest — and in some cases, create personal liability for the executor.

Here is the complete tax calendar for an Oregon estate, with every deadline, extension rule, and consequence mapped out.

Deadline 1: Final Oregon Personal Income Tax Return (Form OR-40)

Due date: April 15 of the year following death.

This is the decedent's last personal income tax return, covering January 1 through the date of death. It follows the same April 15 deadline as any individual return. If the decedent died on September 14, 2025, the final OR-40 covers January 1 through September 14, 2025, and is due April 15, 2026.

Extension: A six-month extension to file moves the deadline to October 15. File IRS Form 4868 (which Oregon accepts) by April 15 or request an extension through Oregon's e-file system. An extension to file is not an extension to pay — if taxes are owed, they must be estimated and paid by April 15 to avoid late payment penalties.

Penalties for missing this deadline:

• Late filing: 5% of the unpaid tax per month, up to 25%
• Late payment: 5% of the unpaid tax per month, up to 25%
• Both can run concurrently, so a return filed and paid late can accumulate up to 47.5% in combined penalties before interest

Oregon kicker: The final OR-40 may carry a refundable kicker credit if the decedent had 2024 Oregon tax liability. At 9.863 percent of prior-year liability, this credit can be substantial. It is only available by actively filing the return — it does not arrive automatically.

Deadline 2: Oregon Estate Tax Return (Form OR-706)

Due date: 12 months after the date of death.

This is the most critical and most commonly miscalendared deadline for Oregon estates. If the decedent died on March 20, 2025, the OR-706 is due March 20, 2026. This differs from the federal Form 706, which is due nine months after death.

Form OR-706 is required if the Oregon gross estate exceeds $1 million. Unlike the federal system, Oregon has no portability between spouses — each spouse's $1 million exemption must be used at the first death or it is lost.

Extension to file: Oregon allows a six-month extension to file, moving the deadline from 12 months to 18 months. Request the extension before the 12-month deadline using Oregon Form OR-706-EXT.

Extension to pay: A separate payment extension may be available, but only under strict conditions and only with written request, detailed justification, and collateral equal to twice the unpaid tax. The Department of Revenue does not grant payment extensions routinely.

Penalties for missing this deadline:

• 5% of the unpaid tax immediately upon missing the due date
• Ongoing interest at the statutory rate (reset quarterly by Oregon)
• The 5% penalty is on the unpaid tax, not the total estate — but on a large estate, this is real money. A $50,000 tax bill generates a $2,500 penalty on day one.

Critical distinction: An extension to file does not extend the time to pay. If you apply for the six-month filing extension, you must still remit the estimated Oregon estate tax by the original 12-month deadline. Filing the extension without paying the estimated tax simply shifts the penalty from late filing to late payment.

Deadline 3: Oregon Fiduciary Income Tax Return (Form OR-41)

Due date: The 15th day of the 4th month after the close of the estate's fiscal year.

This is the most variable deadline because it depends on the fiscal year the personal representative chooses for the estate. Unlike individuals, estates can elect any fiscal year ending on the last day of any calendar month.

Examples:

• Estate with December 31 fiscal year end → OR-41 due April 15
• Estate with January 31 fiscal year end → OR-41 due May 15
• Estate with July 31 fiscal year end → OR-41 due November 15
• Estate with October 31 fiscal year end → OR-41 due February 15 of the following year

Filing is required if:

• The estate has $600 or more in gross income during the tax year
• The personal representative elects to establish a fiscal year, even for a short first year with income below $600
• A nonresident estate earns $600 or more from Oregon sources

Extension: A five-month extension to file is available. For an estate on a December 31 fiscal year, this pushes the deadline from April 15 to September 15.

Oregon-specific modification: Oregon does not conform to all federal rules for fiduciary income tax. OR-41 starts from the federal taxable income figure but requires several Oregon-specific additions and subtractions that must be computed separately.

How These Three Deadlines Can Stack Up Simultaneously

Consider an Oregon estate where someone dies on November 1, 2025:

The personal representative in this scenario has three separate filings with three separate deadlines, each with its own payment obligation, extension rules, and penalty structure. Managing them on a single calendar — with reminders set at least 30 days before each deadline — is essential.

The Order of Priority

Oregon does not require filing all three returns simultaneously or in a fixed sequence, but there is a logical order to manage cash flow:

1. File the final OR-40 first (or simultaneously with the others if deadlines align). This resolves any remaining individual income tax obligation and may generate a refund that flows into the estate.

2. File and pay OR-706 by 12 months. This is the highest-stakes deadline because the penalty is immediate and the amounts can be large.

3. File OR-41 annually until the estate is fully distributed and closed. The last OR-41 is marked as a final return.

What Happens If You Miss a Deadline

Missing the OR-706 deadline generates an automatic 5% penalty and begins accruing interest. For estates near the $1 million threshold where the tax bill might be modest, executors sometimes underestimate how quickly these charges add up on top of attorney and CPA fees.

Missing the OR-40 deadline primarily affects whether the estate can claim any refund owed to the decedent. Refunds on deceased taxpayers' final returns are paid to the estate; delay in filing delays the estate receiving that cash.

Missing the OR-41 deadline is rarely catastrophic unless the estate has significant accumulated income — but the Oregon Department of Revenue will assess penalties and may follow up with an audit notice if returns are consistently late.

Managing three separate tax filing systems on three separate calendars, while simultaneously administering probate, resolving creditor claims, and communicating with beneficiaries, is a large undertaking for any personal representative. The Oregon Final Tax & Estate Tax Guide includes a consolidated deadline tracker and walks through each form in the order you need to handle it.

See more Oregon guides →