Social Security is taxable income for some people, but not all

Whether you owe federal income tax on your Social Security benefits depends on your total income for the year. The IRS uses a formula called "combined income" to decide. If your combined income stays below a certain threshold, you pay no tax on your benefits. If it goes above that threshold, you may owe tax on up to 85 percent of what you received.

Combined income means your adjusted gross income plus nontaxable interest plus half of your Social Security benefits. The threshold amounts have not changed since 1984, so more people cross them each year as wages and benefits rise. Your state may also tax Social Security benefits — rules vary widely by state.

Key Takeaways

  • You owe federal tax on Social Security only if your combined income exceeds $25,000 (single filer) or $32,000 (married filing jointly); these thresholds have been fixed since 1984.
  • Combined income includes your wages, pensions, investment income, and half of your Social Security benefits, not just the benefits themselves.
  • If you cross the threshold, the IRS taxes up to 85 percent of your benefits, not 100 percent.
  • Some states tax Social Security benefits and some do not; your state's rules are separate from federal tax rules.
  • You can reduce the amount of tax withheld by filing a new W-4 form with your employer or by making estimated quarterly tax payments.

How the IRS calculates combined income

Start with your adjusted gross income — this is your wages, self-employment income, pensions, and taxable interest, minus certain deductions like contributions to a traditional IRA. Then add back any nontaxable interest (usually from municipal bonds). Finally, add half of your Social Security benefits for the year.

The result is your combined income. If you are single and it is $25,000 or less, none of your benefits are taxed. If you are married filing jointly and it is $32,000 or less, none of your benefits are taxed. Married people filing separately face a $0 threshold, meaning any combined income at all can trigger taxation.

Once you cross the threshold, the calculation becomes more complex. The IRS taxes the lesser of (1) 85 percent of your benefits, or (2) 85 percent of the amount by which your combined income exceeds the threshold, plus the smaller of two other percentages applied to income in different ranges. Most people in this situation end up paying tax on somewhere between 50 and 85 percent of their benefits.

The two-tier tax system: which benefits get taxed first

The IRS applies taxes in two stages. In the first tier, up to 50 percent of your benefits can be taxed. This applies to the amount of combined income between the base threshold ($25,000 for single filers) and a second threshold ($34,000 for single filers, $44,000 for married filing jointly).

In the second tier, up to an additional 35 percent of your benefits can be taxed. This applies to combined income above the second threshold. Together, the two tiers mean no more than 85 percent of your benefits are ever subject to federal income tax, even if your combined income is very high.

This structure means that if you are just barely over the first threshold, you will owe tax on a smaller portion of your benefits than someone whose combined income is much higher. The exact percentage depends on how far above the threshold you are.

State taxes on Social Security vary widely

Thirteen states tax Social Security benefits to some degree: Colorado, Connecticut, Kansas, Minnesota, Missouri, Montana, Nebraska, New Mexico, Rhode Island, Utah, Vermont, and West Virginia. The other 37 states do not tax Social Security at all.

Among the states that do tax benefits, the rules differ. Some states follow the federal combined income thresholds. Others use their own thresholds or tax all benefits above a certain age. A few states tax benefits the same way they tax other income. You need to check your specific state's rules — a state that does not tax Social Security may still tax other retirement income like pensions or IRA withdrawals.

How to reduce or avoid withholding on your benefits

If you work while receiving Social Security, you can adjust your W-4 form with your employer to reduce the amount of tax withheld from your paycheck. This does not change what you ultimately owe, but it can help you avoid a large tax bill at the end of the year.

If you do not work but still owe tax on your benefits, you can make estimated quarterly tax payments directly to the IRS. Form 1040-ES walks you through calculating what to pay and when. You can also ask the Social Security Administration to withhold taxes directly from your benefits — you fill out Form W-4V and submit it to your local Social Security office. Withholding rates are 7, 10, 12, or 22 percent of your benefit amount.

Another option is to increase income in lower-tax years and decrease it in higher-tax years if you have control over when you receive certain income. For example, if you are deciding when to take a lump-sum payment or bonus, timing it for a year when your other income is lower can reduce the amount of your benefits that get taxed.

What happens if you do not pay tax on your benefits

If you owe tax on your Social Security benefits and do not pay it, the IRS can offset your future benefits to collect the debt. The agency can also pursue standard collection methods like liens or wage garnishment if you have other income. Interest and penalties explore to unpaid taxes.

The IRS does not automatically calculate your tax liability for you. You are responsible for reporting your benefits on your tax return — the Social Security Administration sends you a Form SSA-1099 each January showing what you received. If you do not file a return when you owe tax, the IRS will eventually contact you.

Frequently Asked Questions

Do I have to file a tax return if I only have Social Security income?

Not necessarily. If Social Security is your only income and it is below the filing threshold for your age and filing status, you do not have to file. However, if you have other income or if some of your benefits are taxable, you should file to report it correctly and possibly claim refundable credits.

Can I reduce my combined income to avoid taxes on my benefits?

You can reduce your adjusted gross income by contributing to a traditional IRA or 401(k), which lowers combined income. However, you cannot reduce the amount of Social Security benefits you receive or the half of benefits that counts toward combined income — that is fixed.

If I delay taking Social Security, will I owe less tax?

Delaying benefits means you receive a higher monthly amount when you do start, but you still owe tax based on your combined income in the year you receive them. Delaying does not change the tax rate; it changes the amount you receive and therefore the total tax you might owe.

Are there any Social Security benefits that are never taxed?

Supplemental Security Income (SSI) is never taxed. However, SSI is a different program from regular Social Security retirement or disability benefits. If you receive SSI, you will not receive a Form SSA-1099, and your benefits do not count toward combined income.

What if I moved to a state with no Social Security tax after I retired?

Your tax obligation for the year you move depends on where you lived when you received the benefits. If you moved mid-year, you may owe tax to your former state for the months you lived there. Check both states' rules and file accordingly, or contact a tax professional in your new state.