Plenty of retirees are surprised to learn that Social Security benefits can be taxed at all, and even more surprised at how easily they cross the line. The rules that decide how much of a benefit is taxable were written decades ago and use dollar figures that have never been adjusted for inflation. As pensions, retirement-account withdrawals, and even modest interest income rise year after year, more retirees drift over thresholds that have not moved since the Reagan administration.
The “combined income” formula that decides the tax
Whether benefits are taxed comes down to a number the government calls combined income: a person’s adjusted gross income, plus any nontaxable interest, plus half of their Social Security benefits. The Social Security Administration lays out the tiers that follow. For a single filer, once combined income passes $25,000, up to half of benefits can be taxed; above $34,000, up to 85% of benefits can be taxed. For a married couple filing jointly, the same steps occur at $32,000 and $44,000. The percentages describe how much of the benefit becomes taxable income, not the tax rate itself, but the effect is that a growing share of a retiree’s Social Security check gets pulled into their taxable income.
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Thresholds stuck in the 1980s and 1990s
What makes these limits bite harder every year is that they are frozen. The $25,000 and $32,000 thresholds were set when benefit taxation began in 1983 and took effect in 1984. The higher 85% tier, with its $34,000 and $44,000 marks, was added in 1993. None of those figures has been indexed to inflation since. Nearly every other part of the tax code, from the standard deduction to income-tax brackets, is adjusted upward each year, but these particular numbers stay put. A retiree in 2026 is measured against the same dollar amounts that applied to retirees paying these taxes decades ago, even though prices and typical incomes are far higher today.
Why more retirees get pulled in each year
Frozen thresholds combined with rising incomes produce a slow, steady expansion of who owes. Cost-of-living adjustments raise Social Security benefits themselves, which lifts the “half of benefits” piece of the combined-income formula. Required withdrawals from traditional retirement accounts grow as those balances grow. Even a retiree living carefully can find that ordinary income increases nudge them past $25,000 or $34,000 without any change in lifestyle. Analysts describe this as a form of bracket creep, and it means benefit taxation, once aimed mainly at higher-income retirees, now reaches many with middle-class incomes.
Levers a retiree can actually control
Because the tax turns on combined income, the timing and source of other income offer some room to maneuver. Withdrawals from a Roth IRA do not count toward combined income, so retirees who hold Roth funds can sometimes cover expenses from those accounts in a year they are close to a threshold. Managing the size of traditional-account withdrawals, spacing out the sale of appreciated assets, or using a qualified charitable distribution to satisfy a required withdrawal can each hold combined income down. None of these moves changes the thresholds, but they can influence which side of them a retiree lands on in a given year.
How the tiers play out for a typical retiree
A concrete case shows how quickly the thresholds are crossed. Consider a single retiree collecting $24,000 a year in Social Security, half of which, $12,000, counts toward combined income. If that retiree also draws $20,000 from a traditional IRA, combined income reaches $32,000, past the first $25,000 mark and closing in on the $34,000 line where up to 85% of benefits become taxable. Add a modest pension or a larger required withdrawal and the retiree is fully into the top tier. Nothing about that budget is extravagant, yet a meaningful portion of the Social Security check now counts as taxable income. The example also highlights a quirk worth understanding: it is not the Social Security benefit alone that triggers the tax, but the combination of the benefit with other income. Two retirees with identical benefits can face very different results depending on how much they pull from taxable accounts in a given year.
What to check before it becomes a surprise
The practical risk is discovering the tax only at filing time, after a large withdrawal or a one-time gain has already pushed benefits into the taxable zone. Retirees can ask the Social Security Administration to withhold federal tax from their monthly benefit to avoid an unexpected bill, and they can estimate their combined income before making a big withdrawal rather than after. For those near a threshold, a quick projection each fall, or a conversation with a tax preparer before year-end, can reveal whether a planned withdrawal will drag more of their benefit into taxable income. The thresholds themselves are unlikely to move without an act of Congress, so for now the only variable in a retiree’s hands is the income they choose to recognize each year.
This article was researched and drafted with the assistance of AI and reviewed by The Financial Wire editorial team.
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David M. Keller is a finance writer based in Columbus, Ohio, covering personal finance and consumer-focused economic topics. He earned his degree in journalism from Ohio University and began his career reporting on local business and economic trends for a regional media outlet. Since then, he has contributed to a variety of online publications, focusing on clear, practical coverage of topics such as cost of living, debt, and everyday financial decision-making.
