6 Tax Duties Every Executor Must Handle Before 2026 Filing

I still remember the knot in my stomach the morning I realized I had missed the Form 1041 deadline for my uncle’s estate. It was a simple oversight—I had been busy with probate paperwork and thought the estate’s income was too small to matter. That mistake cost the estate almost $1,200 in late-filing penalties and interest. That’s the moment I learned that being an executor isn’t just about distributing heirlooms; it’s about handling a web of tax duties that can make or break the estate—and your own peace of mind. If you’re an executor facing the 2026 filing season, here are the six tax duties you absolutely must handle before the deadlines hit.

Why Tax Duties Are the Executor’s Make-or-Break Job (and What Happens If You Slack Off)

Let’s be honest: when someone asks you to be an executor, you probably think about funeral arrangements, finding the will, and maybe arguing with siblings over who gets Mom’s china. But the real heavy lifting—and the biggest legal risk—comes from the tax side. As an executor, you’re personally on the hook if you miss a filing deadline, pay beneficiaries before settling tax debts, or accidentally overlook a state inheritance tax. I’ve seen otherwise careful friends get blindsided by a $10,000 penalty because they didn’t file Form 706 for the portability election. The IRS doesn’t care that you were “too busy” or that the will was ambiguous. They hold you responsible. That’s why this checklist isn’t optional—it’s your survival guide for the 2026 filing year.

Duty #1: File the Decedent’s Final Individual Income Tax Return (Form 1040)

This is the first tax duty most executors think of, but it’s easy to get wrong. You need to file a final Form 1040 for the year the person died, covering all income earned from January 1 through the date of death. That includes final paychecks, self-employment income, IRA distributions, dividends, and even that $200 from selling a used car on Craigslist. The deadline is generally April 15, 2026, for a death in 2025—but if the person died after September 30, 2025, the due date shifts to October 15, 2026. Yes, you can request an extension, but if there’s tax due, you still need to pay by April 15 to avoid interest and penalties.

When I handled my aunt’s final return, I nearly forgot to include a small pension payment that arrived two days after she died. That payment actually belonged to the estate, not her final individual return—a common gotcha. Pro tip: if the decedent had already started their own return before passing (say, they had an accountant working on it), you still need to take over and file the final version. The IRS won’t accept a half-finished form from a deceased taxpayer. And don’t forget to check for refunds—many estates miss out on money they’re owed simply because no one files.

Duty #2: File the Estate’s Income Tax Return (Form 1041) If Needed

After the person dies, the estate becomes its own tax entity. If the estate earns more than $600 in gross income during the administration period (interest on a savings account, dividends from stocks, rental income from property), you must file Form 1041. The deadline for a calendar-year estate is April 15, 2026, for income earned in 2025. A key concept here is Distributable Net Income (DNI): the estate gets a deduction for income it distributes to beneficiaries, which means they pay the tax instead. This can save money, but you have to track distributions carefully and issue Schedule K-1 forms to each beneficiary.

One thing that surprised me: if the estate holds assets that generate income—like a rental house—you might need to file Form 1041 even if the total income is under $600, because the IRS looks at gross income, not net. I once helped a friend whose estate earned $650 in bank interest but had $200 in expenses. The IRS still required a return because gross income exceeded the threshold. Don’t assume small income equals no filing.

Duty #3: File the Federal Estate Tax Return (Form 706) If the Estate Is Large Enough

This is the one that trips up most non-professional executors. The federal estate tax exemption for 2025/2026 is likely around $13 million (adjusted for inflation), so only estates above that amount owe tax. But here’s the counter-intuitive part: you may still want to file Form 706 even if the estate is under the exemption—specifically, to elect “portability.” Portability lets a surviving spouse use the deceased spouse’s unused exemption, potentially saving hundreds of thousands in future estate taxes. If you don’t file Form 706 within nine months of death (you can get a six-month extension), you lose that election forever.

In my own practice, I’ve seen executors skip the 706 because they thought the estate was “too small,” only to have the surviving spouse later sell a business or inherit a large life insurance payout, pushing them over the exemption. Filing a “zero-tax” 706 is a paperwork hassle, but it’s cheap insurance. The deadline is nine months from the date of death—no exceptions if you miss it.

Duty #4: Pay Any State Estate or Inheritance Taxes

Federal estate tax gets all the attention, but state taxes can bite you harder because the thresholds are much lower. As of 2026, about a dozen states have an estate tax (Massachusetts, New York, Washington, Oregon, and others), and several have inheritance taxes (Pennsylvania, New Jersey, Maryland). State exemptions can be as low as $1 million (Massachusetts) or even zero in some inheritance tax scenarios. You must check the rules for the state where the decedent lived and where they owned real estate.

I once worked with an executor in Oregon who assumed the $13 million federal exemption protected them—only to discover Oregon’s exemption was $1 million. The estate was worth $1.5 million, triggering a state estate tax bill of over $50,000. The executor had already distributed assets to beneficiaries, and suddenly she was personally on the hook. Don’t let that be you. State deadlines vary, but they’re usually 9–12 months from death. Mark your calendar now.

Duty #5: Notify Creditors and Handle Tax-Related Claims

Under probate law in most states, you must publish a notice to creditors (usually in a local newspaper) and give known creditors direct notice. This includes the IRS. If the decedent owed back taxes from prior years, the IRS becomes a creditor with priority status—often ahead of unsecured creditors and beneficiaries. You cannot distribute estate assets until you’ve settled all tax debts, or you risk personal liability.

Here’s a real-world example: an estate I know had a small bank account and a house. The executor paid the mortgage and gave the remaining cash to the beneficiaries, thinking everything was fine. Six months later, the IRS sent a notice for $8,000 in unpaid taxes from two years before death. Because the executor had already distributed the assets, the IRS pursued her personally. She ended up paying out of pocket. The lesson: always check for prior-year tax liabilities before you hand over a single dollar to anyone.

Also, file Form 56 (Notice Concerning Fiduciary Relationship) with the IRS to officially notify them of your role. This ensures any future IRS correspondence comes to you, not to the decedent’s old address.

Duty #6: Obtain a Tax ID (EIN) for the Estate and Keep Proper Records

The estate is a separate legal entity, so it needs its own Employer Identification Number (EIN) from the IRS. You cannot use the decedent’s Social Security number for estate bank accounts, tax returns, or reporting income to beneficiaries. Getting an EIN is free and takes about 10 minutes online. Do it right after you’re appointed executor—don’t wait until you need to file a return.

Recordkeeping is the unsung hero of executor duties. Keep every bank statement, receipt for funeral expenses, professional appraisal of property, and correspondence with beneficiaries. If the estate is ever audited (and estates with real estate or business interests are more likely to be), you’ll need to document every deduction and distribution. I keep a physical binder plus a cloud folder for each estate I handle. It saved me once when a beneficiary challenged a distribution—I had the signed receipts and tax forms to prove everything was above board. Without those records, I would have been in a he-said-she-said nightmare.

Practical Takeaway

The executor’s role is a thankless combination of grief management, paperwork, and tax law—but you can handle it if you tackle these six duties one by one. Start with the final 1040, check if you need a 1041 or 706, don’t ignore state taxes, settle all debts before distributing assets, and keep meticulous records. And if you’re unsure about anything, pay a CPA or tax attorney for a few hours of advice. That $500 consultation could save you $5,000 in penalties. Bookmark this list before your next filing deadline—you’ll thank yourself later.