The First Tax Season After Losing a Spouse: What's Actually Time-Sensitive

When a spouse dies, the surviving partner faces a set of tax deadlines and elections, several of which are irreversible if missed. The most time-sensitive: filing a joint return for the year of death, electing portability of the deceased spouse's estate tax exemption (due within 9 months, extendable to 15, with late relief up to 5 years), and documenting the step-up in basis on inherited assets before records get harder to reconstruct. Most of the rest can wait, and knowing the difference matters.

When a spouse dies, the surviving partner inherits not just assets but a set of tax deadlines, most of which nobody mentions at the funeral. Some of these deadlines are genuinely urgent. Others feel urgent but aren't.

This guide separates the two, starting with what needs your attention first and working outward to things that can wait weeks or months.

Portability: Do Not Skip This Filing

**The single highest-return tax filing a surviving spouse can make is electing portability -- and missing the deadline can cost your heirs hundreds of thousands of dollars.** Portability lets you claim your deceased spouse's unused federal estate tax exemption and add it to your own, effectively doubling the amount you can pass to heirs estate-tax-free.

The unused amount is technically the Deceased Spousal Unused Exclusion (DSUE), defined under IRC Section 2010(c)(4).

Every person has a federal estate tax exemption: the amount they can pass to heirs without owing estate tax.

Technical detail

In 2025, that exemption is $13.99 million. In 2026, it's $15 million following the permanent extension under the One Big Beautiful Bill Act.

When your spouse dies without using their full exemption -- which is the case for most people -- you can claim the unused portion through portability.

Why most people miss it

Portability is not automatic. You have to elect it by filing an estate tax return for your deceased spouse, even if their estate is well below the exemption threshold and owes no estate tax. The election is made on Form 706, the federal estate tax return. Many people skip this filing because they assume no return is needed when no tax is owed. That assumption can cost their heirs millions of dollars decades later if asset values grow beyond the surviving spouse's single exemption.

Deadlines for the portability election

- **Standard deadline:** 9 months after the date of death - **Extended deadline:** 15 months after death File Form 4768 (Application for Extension of Time to File a Return and/or Pay U.S. Estate Taxes) to get the extension. - **Late election:** Up to 5 years from the date of death, but only if the estate was not otherwise required to file

Technical detail

Rev. Proc. 2022-32 provides a simplified late election process. The IRS grants these automatically without a user fee or lengthy application.

Why this matters even for smaller estates

You don't know what your assets will be worth in 20 or 30 years. Real estate appreciates. Investments compound. Locking in the portability election now costs a few thousand dollars in CPA and preparer fees. Not locking it in could cost your heirs hundreds of thousands in estate taxes that were entirely avoidable.

Step-Up in Basis: Document This Now, Benefit Later

The step-up in basis can eliminate decades of accumulated capital gains taxes on inherited assets -- but only if you document fair market values before records become hard to reconstruct.

When you inherit assets, the IRS resets the "purchase price" to fair market value on the date your spouse died. This reset is called step-up in basis. IRC Section 1014 resets the basis of inherited property to fair market value (FMV) on the date of the decedent's death.

Say your spouse bought shares in an index fund 30 years ago for $50,000. Those shares are worth $400,000 on the date of death. Without step-up, selling them would trigger taxes on $350,000 of gains. With step-up, your new cost basis is $400,000, and if you sold the next day you'd owe nothing.

Community property vs. common law states

How much of the step-up you get depends on your state:

• Community property states (Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin): Both halves of community property get a full step-up, even the surviving spouse's half 26 USC Section 1014(b)(6).
• Common law states (everywhere else): Only the deceased spouse's share of jointly held assets gets the step-up

This is one of the few areas where community property states provide a clear tax advantage.

What to document and when

There is no legal deadline for basis documentation, but the longer you wait, the harder and more expensive records become to reconstruct. Aim to complete this within a few months:

• Brokerage accounts: The custodian typically provides date-of-death values
• Real estate: Get a qualified appraisal
• Family business: You may need a professional valuation

A CPA who works with estates regularly will have a checklist for this.

Filing Status: It Changes More Than Once

You can file jointly for the year your spouse died, then your status shifts -- potentially twice -- over the next two years. Understanding this progression helps you plan for the "widow's tax penalty" before it arrives.

Year of death: Married Filing Jointly

Your filing status in the year your spouse dies is the same as it was before: Married Filing Jointly. Even if your spouse died on January 1, you can file a joint return for that full tax year (IRS Publication 501). Filing jointly almost always produces the lowest tax bill because the income brackets for MFJ are wider than for any other status.

The only exception: if you remarried before December 31 of the same year, you cannot file jointly with the deceased spouse.

Years 1-2 after death: Qualifying Surviving Spouse

For the next two tax years, you may qualify for Qualifying Surviving Spouse (QSS) status, which gives you the same tax brackets and standard deduction as MFJ. QSS was formerly called "Qualifying Widow(er)."

To qualify for QSS, you must meet all three conditions (IRS Publication 501):

• You have not remarried
• You have a qualifying dependent child (or stepchild) who lived with you all year
• You paid more than half the cost of maintaining your household for that year

Year 3 and beyond: Head of Household or Single

After two years (or immediately, if you don't qualify for QSS), your filing status drops to either:

• Head of Household -- if you have a qualifying dependent and pay more than half of household costs
• Single -- otherwise

This transition is where the "widow's tax penalty" shows up. Your income may not have changed much, but the tax brackets just got narrower and the standard deduction got smaller. The same income that was taxed at 22% under MFJ brackets might now hit the 24% bracket as a single filer. A CPA can model this transition in advance so it doesn't surprise you.

Inherited Retirement Accounts: Spouses Get Options Nobody Else Does

As a surviving spouse, you have three choices for an inherited IRA or 401(k) that no other beneficiary gets. The right one depends mostly on your age. Non-spouse beneficiaries are stuck with the 10-year distribution rule under the SECURE Act; you are not.

Option 1: Roll the account into your own IRA. The inherited funds become yours. You delay Required Minimum Distributions until you reach age 73. Under SECURE 2.0, the RMD age increases to 75 starting in 2033. The downside: if you're under 59 and a half and need access to the money, withdrawals from your own IRA are subject to a 10% early withdrawal penalty on top of income tax.

Option 2: Keep the account as an inherited IRA. You can take distributions at any age without the 10% early withdrawal penalty. This is the better choice if you're under 59 and a half and might need the money. The tradeoff is that RMD calculations follow the decedent's schedule, which may require earlier and larger distributions depending on your spouse's age at death.

Option 3: The SECURE 2.0 spousal election. This newer option lets you be treated as the deceased spouse for RMD purposes. It's particularly useful when the deceased spouse was younger than you, because RMDs are calculated based on the younger person's longer life expectancy, producing smaller required distributions.

The practical strategy if you're under 59 and a half

Keep the inherited IRA in its current form (Option 2) to maintain penalty-free access, then roll it into your own IRA once you turn 59 and a half. This gives you the best of both options.

Missed RMD penalties

If you fail to take a Required Minimum Distribution on time, the penalty is 25% of the amount you should have withdrawn.

Technical detail

SECURE 2.0 reduced this from the previous 50% penalty. It drops further to 10% if you correct the shortfall within 2 years (IRS Publication 590-B).

That's steep enough to warrant setting calendar reminders.

Social Security Survivor Benefits: Claiming Strategies Matter

Survivor benefits and your own retirement benefits are two separate entitlements -- and the order in which you claim them can add tens of thousands of dollars in cumulative benefits over a retirement.

If your spouse worked long enough to qualify for Social Security Typically 10 years or 40 credits., you're eligible for survivor benefits starting at age 60, or age 50 if you're disabled (SSA Survivor Benefits).

The amount depends on your age when you start claiming:

The sequencing strategy most people miss

Because survivor benefits and your own retirement benefits are separate, you can claim one first and switch to the other later if it would be higher. For example, if your own retirement benefit at 70 would exceed your survivor benefit at FRA, you might:

1. Claim the survivor benefit at 60 (even at the reduced rate)
2. Switch to your own retirement benefit at 70 when it's maximized by delayed retirement credits

Two administrative items easy to miss

• Lump-sum death payment: A one-time $255 payment from Social Security. You must apply within 2 years of the date of death (SSA Lump Sum Death Payment).
• Retroactive benefits: The application deadline for retroactive survivor benefits is generally 2 years from the date of death, though you can apply later for prospective benefits.

Social Security taxation: the other "widow's tax penalty"

When you shift from joint to single filing, the same Social Security income can become significantly more taxable. The thresholds for taxing Social Security benefits are much lower for single filers (IRS Publication 915):

Combined income = adjusted gross income + nontaxable interest + half your Social Security benefits.

This gap means the same Social Security check can feel noticeably smaller after you lose joint-filing status.

Estate Administration: The IRS Paperwork

**If your spouse's estate will receive any income after the date of death -- interest, a final paycheck, dividends -- you'll need to handle a handful of IRS filings.** Here is what to do and in what order.

Get an EIN for the estate

The estate is a separate taxpayer. You need an Employer Identification Number before you can open an estate bank account or file estate tax returns. You can get one online from the IRS in about 10 minutes (IRS EIN Online Application).

Establish your authority as executor

File a notice telling the IRS that you (or another executor) are authorized to act on behalf of the deceased taxpayer's estate. This ensures IRS correspondence goes to the right person.

Technical detail

File Form 56 (Notice Concerning Fiduciary Relationship). There is no hard deadline, but file as soon as the executor is appointed (IRS Form 56 Instructions).

File the estate income tax return if needed

If the estate earns $600 or more in gross income during its administration, you must file an estate income tax return.

Technical detail

Form 1041 (Estate Income Tax Return). Due April 15 of the year following the estate's tax year end. The estate can elect a fiscal year rather than a calendar year, which gives flexibility in timing income recognition (IRS Publication 559).

One planning note: estate tax rates are compressed. Estate income hits the top 37% bracket at just $15,650 in 2025, compared to $626,350 for individual filers. Distributing income to beneficiaries (who are likely in lower brackets) is a legitimate planning strategy.

File the estate tax return

As discussed in the portability section, you should file the estate tax return even if the estate is below the exemption threshold, in order to elect portability.

Technical detail

Form 706 is required if the gross estate exceeds the exemption threshold ($13.99 million in 2025). Deadline: 9 months from date of death, extendable to 15 months with Form 4768.

State Estate and Inheritance Taxes: The Other Layer

Federal estate tax gets the headlines, but state-level taxes catch more people because the exemptions are often far lower.

State estate taxes

Twelve states and the District of Columbia impose their own estate tax, with exemptions well below the federal level:

• Oregon: $1 million exemption
• Massachusetts: $2 million
• New York: $7.16 million, but has a "cliff" -- if the estate exceeds the exemption by more than 5%, the entire estate is taxed from dollar one
• Also impose estate taxes: Connecticut, Hawaii, Illinois, Maine, Maryland, Minnesota, Rhode Island, Vermont, Washington, and the District of Columbia, each with their own exemptions and rates

State inheritance taxes

Five states tax the people who receive the inheritance rather than the estate itself:

• Kentucky, Maryland, Nebraska, New Jersey, and Pennsylvania

Iowa phased out its inheritance tax effective January 1, 2025.

The rate typically depends on the beneficiary's relationship to the deceased. Spouses are usually exempt; distant relatives or non-relatives pay the highest rates.

Maryland has both

Maryland is the only state that imposes both an estate tax and an inheritance tax, though there are credits to avoid full double taxation.

Multi-state property

If your spouse owned property in multiple states, you may owe estate or inheritance tax in each state where property is located, even if you live in a state with neither tax. This is worth checking with a CPA who handles multi-state estates.

Deadline Summary

When to Get Professional Help

A CPA who works with surviving spouses regularly can tell you which of these rules apply to your specific situation in about 10 minutes. That's not an exaggeration. The variables are your age, your spouse's age, your state, how assets were titled, whether there are retirement accounts, and the size of the estate. A practiced CPA has seen your configuration before and knows exactly which elections to file and which deadlines to prioritize.

What makes this situation different from routine tax work is the interaction between the rules. Portability affects estate planning. Filing status affects Social Security taxation. Step-up in basis affects whether you should sell inherited investments this year or hold them. The inherited IRA decision depends on your age and cash needs. These pieces don't exist in isolation, and a CPA who handles this regularly will coordinate them rather than treating each as a separate checkbox.

The cost of this planning session is typically a few hundred dollars. The cost of missing a portability election or failing to document step-up in basis can be orders of magnitude higher.