Social Security and Medicare are taxed differently — and not always the way you expect

Social Security benefits may be taxed as federal income, but Medicare premiums are not. However, Medicare Part B and Part D premiums are deducted from your Social Security check before you receive it, which means you pay them with pre-tax dollars. The amount of Social Security that counts as taxable income depends on your other earnings and a formula called "combined income." Medicare premiums themselves do not reduce your taxable income on your federal return.

This distinction matters because it affects both what you owe in taxes and what you actually receive each month. Understanding which parts are taxable and which are deducted helps you plan for the taxes you may owe at the end of the year.

Key Takeaways

  • Up to 85 percent of your Social Security benefits may be taxable federal income, depending on your combined income from all sources.
  • Medicare Part B and Part D premiums are deducted directly from your Social Security payment before you receive it, but these deductions do not lower your taxable income.
  • You receive a Form SSA-1099 each January showing how much Social Security you received and how much was taxable.
  • If you work while receiving Social Security before full retirement age, some benefits may be withheld, and this affects your tax calculation.
  • You may owe federal income tax on Social Security even if no tax was withheld from your check.

Which part of Social Security counts as taxable income

The IRS uses a formula called combined income to determine how much of your Social Security is taxable. Combined income is the sum of your adjusted gross income, non-taxable interest, and half of your Social Security benefits.

If your combined income is below $25,000 (single) or $32,000 (married filing jointly), none of your Social Security is taxable. If it exceeds those thresholds, up to 50 percent of your benefits may be taxable. If your combined income exceeds $34,000 (single) or $44,000 (married filing jointly), up to 85 percent of your benefits may be taxable. These income thresholds have not changed since 1984.

Combined income includes wages, pensions, interest, dividends, rental income, and income from part-time work. It also includes non-taxable interest from municipal bonds. This is why a modest pension or part-time job can push you into a tax bracket where Social Security becomes taxable.

How Medicare premiums are deducted from your Social Security

If you receive Social Security and are enrolled in Medicare Part B (medical insurance) or Part D (prescription drug coverage), your premiums are deducted from your monthly Social Security payment. Most people pay the standard Part B premium, which is $164.90 per month in 2024, though this amount changes each year. Part D premiums vary by plan and range from roughly $7 to $100 per month depending on which plan you choose.

These deductions happen before you receive your check, which means you never see that money. However, the deductions themselves do not reduce the amount of Social Security that is counted as taxable income on your federal tax return. The IRS counts your full Social Security benefit before any Medicare premium deduction when calculating your combined income and your taxable portion.

If you have higher income, you may also pay an Income-Related Monthly Adjustment Amount (IRMAA) on top of your standard Part B and Part D premiums. IRMAA is based on your income from two years prior and can add $70 to $560 per month to your Part B premium depending on your income level. This adjustment is also deducted from your Social Security check.

What happens if you work while receiving Social Security

If you have not yet reached your full retirement age and you work, Social Security withholds $1 in benefits for every $2 you earn above $23,400 per year (in 2024). In the year you reach full retirement age, the withholding is $1 for every $3 you earn above $62,160 until the month you turn full retirement age. Once you reach full retirement age, you can earn any amount with no withholding.

The benefits that are withheld are not paid to you, but they are still counted in your combined income for tax purposes. This means you could owe federal income tax on Social Security benefits you never actually received. The IRS counts the full amount of benefits you were may have access to to receive, not just the amount you actually got after withholding.

Understanding your Form SSA-1099

Each January, the Social Security Administration sends you a Form SSA-1099 showing how much Social Security you received in the previous year. Box 1 shows your total benefits before any Medicare deductions. Box 2a shows the taxable portion that Social Security calculated, though this is not always correct for your specific tax situation.

You will use the amount in Box 1 (your total benefits) when you file your federal tax return, not the amount in Box 2a. The Social Security Administration's calculation of taxable benefits is an estimate and may not account for all your income sources or your filing status. Your tax preparer or tax software will recalculate the taxable portion using the combined income formula and your actual income for the year.

If you did not receive a Form SSA-1099 by early February, contact Social Security at 1-800-772-1213 to request a replacement. You will need this form to file your federal return accurately, even if you did not owe taxes in previous years.

When you may owe taxes even with no withholding

Social Security does not automatically withhold federal income tax from your benefits. If you expect to owe taxes on your Social Security, you can request voluntary withholding by completing Form W-4V and submitting it to Social Security. You can choose to have 7, 10, 12, or 22 percent of your monthly benefit withheld.

Many people do not request withholding and then owe taxes when they file. This happens most often when you have other income — a pension, part-time work, investment income, or a spouse's income — that pushes you into a tax bracket where Social Security becomes taxable. You may also owe if you received a large one-time payment, such as a retroactive benefit adjustment.

If you did not have enough tax withheld during the year, you can make estimated tax payments to the IRS quarterly, or you can wait and pay the full amount when you file your return. Owing taxes on Social Security is common and does not trigger any penalty as long as you pay by the tax important date or file for an extension.

How to plan ahead for Social Security taxes

The best time to think about Social Security taxes is before you claim benefits. If you have a pension or plan to work part-time in retirement, ask a tax professional how much of your Social Security will be taxable. This helps you decide whether to request voluntary withholding or set aside money for taxes.

If you are already receiving Social Security and owed taxes last year, you can adjust your withholding by submitting a new Form W-4V to Social Security. You can increase or decrease the withholding percentage, or stop it altogether. Changes take effect with your next payment after Social Security processes your request, which usually takes one to two months.

Keep copies of your Form SSA-1099 and any tax returns you file showing Social Security income. If you ever need to verify your income for a loan, housing, or other purpose, these documents prove what you reported to the IRS.

Frequently Asked Questions

Do I have to pay federal income tax on Social Security?

Not necessarily. If your combined income is below $25,000 (single) or $32,000 (married filing jointly), you owe no federal income tax on Social Security. If your combined income is higher, up to 85 percent of your benefits may be taxable. Combined income includes wages, pensions, interest, dividends, and half of your Social Security benefits.

Are Medicare premiums deducted before or after taxes?

Medicare Part B and Part D premiums are deducted from your Social Security check before you receive it, using pre-tax dollars. However, these deductions do not reduce the amount of Social Security counted as taxable income on your federal return. The IRS counts your full benefit before any Medicare deduction.

What if Social Security withheld benefits because I worked too much?

Withheld benefits still count as income for tax purposes. The IRS taxes the full amount you were may have access to to receive, not just what you actually got. You may owe federal income tax on benefits you never received. When you reach full retirement age, the withholding stops and you receive your full benefit.

Can I request that taxes be taken out of my Social Security check?

Yes. Complete Form W-4V and send it to your local Social Security office or mail it to Social Security. You can choose to have 7, 10, 12, or 22 percent of your monthly benefit withheld for federal income tax. You can change or stop the withholding at any time by submitting a new form.

What should I do if I owe taxes on Social Security?

You can pay the full amount when you file your return, make quarterly estimated tax payments to the IRS, or request voluntary withholding going forward. Owing taxes on Social Security does not result in a penalty as long as you pay by the tax important date or file for an extension. A tax professional can help you decide which option works best for your situation.