Taxes on Social Security Benefits: The Part Nobody Warns You About

Finding out that Social Security benefits can be taxed is one of the bigger surprises people run into in retirement. You paid into the system for decades, you filed for your benefit, and then your tax preparer tells you that a portion of it counts as taxable income. It feels wrong. And even if it's not wrong, it would have been nice to know.

This is one of the most common things we hear in the Retirement Clarity Community. So let's walk through how it actually works, what the thresholds are, and what you can do to manage it.

The Short Version

Up to 85% of your Social Security benefit can be taxable. Not all of it — and for some people, none of it. The percentage depends on your "combined income," which the IRS calculates by adding your adjusted gross income, any nontaxable interest, and half of your annual Social Security benefit.

That number determines which bracket you fall into. It's not intuitive, but once you see the math, it makes sense.

How Combined Income Works

The IRS uses a specific formula to figure out how much of your benefit is taxable. They call the key figure "combined income," though you may also see it called "provisional income."

Here's what the thresholds look like for 2025:

Single filers:

• Combined income below $25,000: no Social Security tax
• Combined income between $25,000 and $34,000: up to 50% of your benefit may be taxable
• Combined income above $34,000: up to 85% of your benefit may be taxable

Married filing jointly:

• Combined income below $32,000: no Social Security tax
• Combined income between $32,000 and $44,000: up to 50% of your benefit may be taxable
• Combined income above $44,000: up to 85% of your benefit may be taxable

One thing worth noting: these thresholds have not been adjusted for inflation since they were set in 1983 and 1993. A combined income of $34,000 felt different forty years ago. Today, many people who would not consider themselves high earners cross these lines without realizing it.

A Real Example

Take a couple both aged 68. Their combined Social Security benefit is $36,000 per year. They also have $28,000 in withdrawals from a traditional IRA.

Their combined income calculation looks like this:

• Adjusted gross income from IRA withdrawals: $28,000
• Half of Social Security: $18,000
• Combined income: $46,000

That puts them above the $44,000 joint threshold, which means up to 85% of their Social Security benefit ($30,600) could be counted as taxable income. They are not wealthy. They are not living extravagantly. They just have the kind of income mix that many retired couples have, and nobody told them this was coming.

What Actually Triggers the Tax

A few income sources tend to push people over the thresholds without them expecting it.

Traditional IRA or 401(k) withdrawals. Any money you pull from a pre-tax retirement account counts toward your adjusted gross income. This is the most common trigger. Required minimum distributions — the withdrawals the IRS requires you to start taking from traditional accounts at age 73 — can push your combined income up significantly, even if you do not need the money that year.

Part-time work or consulting income. If you are working part-time in the early years of retirement, that earned income adds to your total.

Pension income. Monthly pension payments count as ordinary income and go straight into the calculation.

Investment income. Interest from savings accounts, dividends from taxable brokerage accounts, and capital gains from selling investments all factor in.

Nontaxable interest. This one surprises people. Interest from municipal bonds is federally tax-exempt, but it still counts in the combined income formula. It will not be taxed, but it can push more of your Social Security into taxable territory.

What You Can Do About It

There is no one right answer here, but there are a few approaches worth understanding and discussing with a tax professional.

Roth conversions before you claim Social Security. If you retire at 62 but plan to delay claiming Social Security until 67 or 70, those years in between are often a good window. Your income may be lower, and you can convert traditional IRA money to a Roth IRA — paying tax now, at potentially lower rates — before Social Security income enters the picture. Future Roth withdrawals do not count toward combined income at all.

Managing IRA withdrawals strategically. Rather than waiting until required minimum distributions force large withdrawals at 73, some people take smaller, voluntary withdrawals in their 60s to keep taxable balances lower later. The goal is to avoid large spikes in income that push more of your Social Security into taxable territory.

Timing other income carefully. If you have a year where you plan to sell investments or take a large IRA distribution, it may make sense to factor in how that affects your combined income and, in turn, how much of your Social Security gets taxed that year.

Withholding or quarterly payments. If you are already collecting Social Security, the IRS lets you request voluntary withholding from your monthly benefit to cover the tax liability. You can set this up through the Social Security Administration usingIRS Form W-4V. Some people prefer this over making quarterly estimated tax payments separately.

A Few Things This Article Cannot Do

The math above is real and the thresholds are accurate, but your specific situation involves factors this article cannot account for: your filing status, your full income picture, state taxes (some states tax Social Security benefits, others do not), and any deductions that reduce your adjusted gross income.

Before making decisions about Roth conversions, IRA withdrawals, or withholding elections, it is worth sitting down with a CPA or tax professional who can run the numbers for your household.

For official guidance, the IRS has a straightforward page on Social Security taxation atIRS.gov, and the Social Security Administration covers the basics atSSA.gov.

The Main Thing to Take Away

Most people approaching or entering retirement do not realize that Social Security income interacts with their other income sources in a way that can affect their tax bill. It is not a penalty. It is just a formula that was designed at a time when far fewer people crossed those thresholds.

Knowing how combined income works gives you something useful: the ability to plan for it, and in some cases, to manage it. Whether your tax exposure is small or significant, understanding the rules puts you in a better position than being surprised at tax time.