This is part four of The Gap Years. We have looked at the window itself, at filling your tax bracket with Roth conversions, and at the Medicare surcharge that remembers your income from two years ago. Today we turn to a surprise that catches almost everyone, because it feels like it should not be allowed: your own Social Security benefit, the money you paid in for decades, can be taxed when it comes back to you.
Do you have to pay taxes on Social Security?
For many retirees, yes. Depending on your income, up to 85 percent of your Social Security benefit can be pulled into your taxable income and taxed at your ordinary rate. Notice the wording, because it trips people up. It is not that 85 percent of your benefit disappears in tax. It is that as much as 85 percent of the benefit gets added to the income you pay tax on. How much depends entirely on a number the government calls your combined income.
How the tax actually works
Your combined income, sometimes called provisional income, is your other income plus any tax-exempt interest plus one half of your Social Security benefit. The IRS then runs it against two thresholds. For a married couple filing jointly, if that number lands above 32,000 dollars, up to half of your benefit becomes taxable. If it lands above 44,000 dollars, up to 85 percent of it does. For a single filer the two lines are 25,000 and 34,000 dollars. The more other income you have, from a pension, a withdrawal, a conversion, the more of your Social Security gets dragged onto the taxable side of the ledger.
The thresholds that never move
Here is the quiet part. Those dollar figures, the 25,000 and 32,000 and 34,000 and 44,000, were written into law in 1993 and have never been adjusted for inflation, not once. A couple with 44,000 dollars of combined income in 1993 was comfortably middle income. More than thirty years of rising prices later, the line sits in exactly the same place, which means it now catches retirees it was never built to catch. Nothing about the rule changed. The world around it did. This is a tax that quietly widens every single year simply by standing still.
But did the new law not make Social Security tax-free?
This is worth clearing up carefully, because the headlines created real confusion. The 2025 tax law, often called the One Big Beautiful Bill, did not repeal the taxation of Social Security. The rules above are still fully in force. What the law actually did was create a separate, temporary deduction for people 65 and older, and it is generous enough that many lower and middle income retirees will owe no federal tax on their benefits in practice. But it works by lowering your overall taxable income, not by making Social Security itself tax-free. And it has two catches that matter for our readers: it begins to phase out once income climbs past 75,000 dollars for a single filer or 150,000 dollars for a couple, and it is scheduled to expire after 2028. For a higher income household, the old taxation rules still apply in full. So if you heard that Social Security is now tax-free and assumed you were done thinking about it, it is worth a second look. And because this provision is brand new and the guidance around it is still developing, the specifics are worth reviewing with a tax professional rather than taken from a headline.
The tax torpedo
There is a mechanism here with a dramatic name that it has genuinely earned. Once your Social Security is switched on, each extra dollar of income you create can push another 50 to 85 cents of your benefit into the taxable column at the same time. So that one dollar is taxed, and it also drags part of your previously untaxed benefit into tax alongside it. The result is that your true tax cost on that dollar can be noticeably higher than the bracket you think you are in. Advisors call it the tax torpedo, and it is one of the strongest arguments for doing the heavy lifting, like Roth conversions, during the early gap years before you turn Social Security on, while there is no benefit sitting there to be dragged into the blast.
How much of my Social Security is taxable?
Up to 85 percent of your benefit can be included in your taxable income, though many retirees fall in the zero or 50 percent range. The amount depends on your combined income, which is your other income plus any tax-exempt interest plus half of your benefit. Below 25,000 dollars single or 32,000 dollars joint, none of it is taxed. Above 34,000 single or 44,000 joint, up to 85 percent can be. It is taxed at your ordinary income rate, not at a flat 85 percent.
Is Social Security tax-free now under the new law?
Not as a rule. The 2025 law did not repeal the taxation of benefits. It created a temporary deduction for those 65 and older that, in practice, wipes out the tax for many lower and middle income retirees by reducing their overall taxable income. But it phases out above 75,000 dollars of income for singles and 150,000 dollars for couples, and it expires after 2028, so higher income households are still fully subject to the original rules.
What is the Social Security tax torpedo?
It is the way an extra dollar of income can cause part of your Social Security benefit to become taxable at the same time, so a single added dollar effectively gets taxed more than once over. It can lift your real marginal tax rate well above your stated bracket within a certain income band. Planning withdrawals and conversions with the torpedo in mind, often before Social Security begins, is how people work around it.
So your Social Security really can be taxed, sometimes heavily, and the rules are quirky enough that they reward anyone willing to plan around them rather than be surprised by them. This is also why the pieces of this series fit together: the conversion you make in part two, the IRMAA line in part three, and the Social Security torpedo here all run on the same fuel, which is your taxable income for the year. Tomorrow, in the final part, we pull all of it into one picture and talk about how to actually draw your retirement paycheck in a tax-smart order. If you want to see how these thresholds line up against your own income, you can reach our team at American Retirement Advisors at 602-281-3898. Tomorrow, part five: putting it all together.
Disclaimer: The information in this article is for educational purposes only and does not constitute tax, legal, or investment advice. Tax laws change frequently, and individual circumstances vary. American Retirement Advisors does not provide tax or legal services. Before making any tax-related decisions, consult a qualified CPA, tax attorney, or financial planner who can evaluate your specific situation.