By LIZ WESTON of NerdWallet

After a spouse dies, the survivor often ends up paying higher taxes on less income __ something known by accountants and financial planners as the "widow's penalty," because women typically outlive their husbands.

Couples who know what's coming often can take steps to soften the penalty's effect, but too many don't think far enough ahead, says Barbara O'Neill, a certified financial planner and educator in Ocala, Florida.

"A lot of people just underestimate what the impact will be financially," O'Neil says.

INCOMES PLUNGE BUT EXPENSES MAY NOT

A spouse's death often leads to a substantial drop in income. Wages or salary typically end if the deceased spouse was still working, and many people don't have enough life insurance to replace that loss.

If a couple is retired and receiving Social Security, the benefit amount can drop by one third to one half. The survivor gets the larger of the two checks the couple received, and the smaller benefit goes away. If the deceased spouse received pension or annuity payments, the survivor may get a reduced amount or nothing at all, depending on what payout option the couple chose.

The income decline may be offset by lower expenses, such as reduced bills for groceries or auto insurance for one vehicle instead of two, says O'Neill, author of "Flipping a Switch: Your Guide to Happiness and Financial Security in Later Life." But some expenses could go up. The survivor may hire help to perform some of the chores the deceased previously handled, for example. Or they may want to subscribe to a medical alert service now that they're living alone, she says.

And then there are the tax bills.

TAXES AND MEDICARE PREMIUMS CAN CHANGE AFTER A DEATH

A surviving spouse can use the favorable "married filing jointly" status in the year their partner dies, as long as the survivor doesn't remarry before the year ends. After that, survivors without dependent children are typically forced to use the less favorable "single" filing status.

The standard deduction for a married couple __ $27,700 in 2023 __ is twice that of a single person. Plus, taxpayers who are married filing jointly can have taxable income up to $89,450 and remain in the 12% federal tax bracket. That bracket ends at $44,725 for single filers. The next tax bracket is 22%.

Survivors receiving Social Security can find that more of their benefit gets taxed. Up to 85% of Social Security benefits are taxable if "combined income" __ adjusted gross income, plus nontaxable interest, plus half of Social Security benefits __ exceeds $44,000 for a couple. For a single person, the limit is $34, 000.

Survivors on Medicare might see their premiums rise, thanks to a surcharge known as the income-related monthly adjustment amount, or IRMAA.