The Unwanted Surprise Lurking Behind 2027’s Social Security COLA

If you're excited about the idea of a 3.6% Social Security cost-of-living adjustment, or COLA, in 2027, that makes a ton of sense. This year, benefits only increased by 2.8%, and inflation quickly eroded that raise as prices soared on the heels of the Middle East conflict. A 3.6% raise may seem like a more comfortable bump.

But there's a hidden problem with next year's 3.6% Social Security COLA. You may not feel it right away, but it could eventually come back to bite you.

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Larger benefits increase the chances of taxes

Many Social Security recipients don't pay taxes on their monthly benefits. Whether those taxes apply depends on provisional income, which is calculated as the total of adjusted gross income, tax-exempt interest income, and 50% of seniors' annual Social Security benefits.

Once provisional income reaches $25,000 for single filers and $32,000 for married couples filing taxes jointly, taxes on Social Security benefits can apply. And if you're thinking these limits are extremely low, you'd be right. Congress established them decades ago to help shore up Social Security's finances, and they have not gotten an inflation adjustment since.

Now, here's where a generous COLA comes into play. A 3.6% raise will boost Social Security benefits nicely. But since those benefits are part of the provisional income formula, a large COLA could also lead to more people owing federal taxes on their benefits -- if not in 2027, then eventually.

Thanks to the One Big Beautiful Bill Act, many older Americans are currently eligible for a $6,000 senior deduction. As such, taxes on Social Security may not be a problem now so much as in 2028, when that $6,000 deduction is scheduled to expire.

Once that happens, more people could owe taxes on their Social Security checks, especially if the next couple of COLAs are also on the generous side. So it's important to know that taxes on benefits exist and prepare for them.

Don't get thrown for a loop

The way to earn Social Security benefits is to pay taxes on wages throughout your career. Based on that, you might assume that your Social Security checks are yours to enjoy tax-free in retirement.

But Social Security relies on tax revenue to keep up with benefit payments, and that extends to taxes on benefits themselves. It's important to know what the provisional income thresholds entail, and to recognize that as more generous COLAs are applied to Social Security, the chances of having your benefits taxed may increase.

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