Why a Surviving Spouse Can Get Hit With a Bigger Tax Bill — and How to Reduce It

Quick Read

• When one spouse dies, the survivor files as single, deductions shrink sharply, and federal tax on a $1.2 million IRA pair can nearly double.

• Moving roughly $48,000 a year into a Roth while both spouses are alive can keep income in the 12% bracket and help protect the survivor later.

• Delaying the higher earner’s Social Security until age 70 and keeping bonds inside the IRA can also improve the survivor’s after-tax income over time.

Many married couples map out retirement together, but the tax system does not treat them that way for long. After one spouse dies, the survivor generally files a single return, and the tax picture can change fast: the standard deduction is cut in half, the extra deduction for those over 65 is reduced, the senior deduction is smaller, brackets narrow, and more Social Security becomes taxable. Income often falls only modestly, while deductions drop much more.

Advisers often call this the widow’s penalty, though widowers face it too. It is foreseeable and often substantial, and the main fix has to happen while both spouses are still living. Here is an example involving a couple who are 68 and hold $1.2 million in traditional IRAs.

The couple’s tax return now

Both are retired. He receives $3,200 a month from Social Security, while she receives $1,900, for a combined $61,200 a year. They take 4% from the IRAs, or $48,000, and the rest of their assets are invested in an S&P 500 fund and Treasuries.

On a joint return, the Social Security worksheet counts their $48,000 of other income plus half of their benefits, or $78,600 total, against the $44,000 threshold for couples. That means $35,410 of their $61,200 in benefits is taxable, leaving adjusted gross income at $83,410.

They then claim a $32,200 standard deduction, $1,650 each for being over 65, and $6,000 each from the senior deduction that is available through 2028. Altogether, that reduces income by $47,500. Taxable income comes to $35,910, all within the 10% and 12% brackets. Federal tax is about $3,800 on $109,000 of cash flow.

How the survivor return changes

Now he dies. She keeps the home, the IRAs, which she inherits and rolls into her own name, and the larger Social Security check. Her own $1,900 monthly benefit stops, so her Social Security income drops to $38,400 a year from $61,200.

Her costs do not fall by a third. Property taxes, insurance, the car, and utilities remain much the same. She continues to withdraw the same $48,000 from the IRA.

In the year of his death, she can still file jointly. Beginning the following year, she files as single unless she has a dependent child at home, which she does not. That first single return looks very different.

The Social Security worksheet now uses single thresholds of $25,000 and $34,000. Her $48,000 of IRA income plus half of her $38,400 benefit equals $67,200, far above the line, so the full 85% of her benefit becomes taxable: $32,640. Adjusted gross income is $80,640.

Her deductions are the single standard deduction of $16,100, the single over-65 deduction of $2,050, and a senior deduction that is now $6,000 instead of $12,000 and begins phasing out above $75,000 of income for a single filer. Because she is $5,640 above that mark, the deduction falls to $5,662. Her total deductions drop to $23,812, about half what the couple had together.

That leaves taxable income of $56,828. Since the single 12% bracket ends at $50,400, roughly $6,400 is taxed at 22%. Federal tax rises to about $7,200.

Her cash income falls from $109,200 to $86,400, but her federal tax bill climbs from $3,800 to $7,200. The effective tax rate on incoming cash more than doubles, from 3.5% to 8.3%. The situation worsens again at 73, when required minimum distributions begin. If the IRA grows to $1.3 million, the first required withdrawal would be about $49,000, which is close to what she is already taking, but the divisor keeps shrinking each year while single brackets and deductions remain fixed.

What can be done while both spouses are alive

The reason the survivor gets hit so hard is that the money remains in a traditional IRA, where every withdrawal is taxed as ordinary income on a single return. The way to ease that future burden is to shift money out of that account while the couple can still use the joint brackets and doubled deductions, by converting to a Roth IRA.

There is room to do that. On the joint return, taxable income is $35,910, and the 12% bracket extends to $100,800. Every conversion adds income, and the first $19,500 or so also pushes more Social Security into taxable income until the 85% limit is reached. In practice, about $48,000 a year can be converted before any income is taxed above 12%. That keeps adjusted gross income near $148,000, just under the $150,000 level where the senior deduction starts shrinking for couples.

At 12%, a $48,000 Roth conversion creates about $5,800 of tax a year. Repeat that for five years, from age 68 to 73, and about $240,000 moves into Roth accounts for roughly $29,000 in total tax. That money will never be taxed again, will not count toward required withdrawals, and will not appear on the survivor’s single return.

If the survivor later has $240,000 less in the traditional IRA and spends the same amount, required withdrawals at 73 fall by about $9,000 a year. If she uses part of her $48,000 annual withdrawal from the Roth, her taxable income can drop out of the 22% bracket entirely. That can save roughly $2,000 to $3,000 a year for the rest of her life, in exchange for taxes paid now at 12%.

Two more planning moves

One step is to claim the larger Social Security benefit as late as possible. The survivor keeps the higher payment, so if the higher earner waits until 70, that boosts the income the survivor will rely on for years, without creating any tax cost.

Another is to keep the bond portion of the portfolio inside the IRA and hold the stock fund in a taxable account, where gains are taxed at lower capital-gains rates and can receive a stepped-up basis at death. With a 10-year Treasury yielding 4.95%, the interest is usually better sheltered, while stock growth is often better placed where the survivor can sell with little or no tax.

Bottom line

For a 68-year-old couple with $1.2 million in traditional IRAs, federal tax for the surviving spouse can roughly double after the first death, from about $3,800 to about $7,200, even though income is lower. Converting about $48,000 a year to a Roth while both spouses are alive and both sets of deductions still apply costs 12% now and can remove much of that future tax hit. It is one of the few retirement planning moves that has a deadline no one can see.