What the Medicare Surtax Is

The Medicare surtax is an extra 0.9% tax on wages and self-employment income, plus a 3.8% tax on certain investment income. It was created by the Affordable Care Act in 2013 and applies only to higher earners — not everyone pays it. The surtax funds Medicare Part A (hospital insurance) and is separate from the regular 2.9% Medicare tax that nearly all workers pay.

The key difference: the regular Medicare tax applies to all wages with no income limit. The surtax only kicks in once your income crosses a threshold that depends on your filing status and whether you are married. If you earn below that threshold, you will not owe the surtax at all.

Key Takeaways

  • The Medicare surtax is 0.9% on wages and 3.8% on investment income, and it only applies to people whose income exceeds $200,000 (single filers) or $250,000 (married filing jointly).
  • Your employer withholds the 0.9% wage surtax automatically if your pay crosses the threshold, but you may owe more at tax time if you have multiple jobs or investment income.
  • The 3.8% surtax on investment income applies to capital gains, dividends, rental income, and other unearned income above the threshold.
  • You report the surtax on your federal tax return using Form 8960; it is not a separate payment but part of your overall tax bill.

The Income Thresholds That Trigger the Surtax

The surtax applies only if your income exceeds specific amounts set by filing status. For single filers, the threshold is $200,000. For married couples filing jointly, it is $250,000. For married filing separately, it is $125,000. These thresholds have not changed since 2013 and do not adjust for inflation each year.

The income that counts toward the threshold includes wages, self-employment income, and certain investment income. If you are close to the threshold, you need to know exactly what counts. Wages from your job count. So do net profits from self-employment, rental income, capital gains from selling stocks or property, and dividends. Social Security does not count, nor do distributions from traditional IRAs or 401(k)s (though the income you earned to make those contributions did count when you earned it).

The 0.9% Wage Surtax: How Withholding Works

If you are an employee and your wages cross the threshold, your employer should withhold the 0.9% surtax from your paycheck automatically. The withholding begins once your cumulative wages for the year exceed $200,000 (or $250,000 if married filing jointly). Your employer uses the threshold for your filing status, which you provide on your W-4 form.

The problem arises when you have multiple jobs. If you work two part-time jobs and earn $130,000 at one and $80,000 at the other, neither employer may withhold the surtax because neither sees income above the threshold. You will owe the surtax at tax time, and you must pay it yourself. This is why people with multiple jobs or spouses who both work should check their combined withholding during tax season.

Self-employed people do not have an employer to withhold, so they owe the surtax directly when they file their return. You calculate it on Form 8960 and add it to your tax bill.

The 3.8% Investment Income Surtax

The second part of the Medicare surtax is 3.8% on net investment income. This applies to capital gains (profit from selling stocks, real estate, or other assets), dividends, interest, rental income, and royalties. Like the wage surtax, it only applies if your total income exceeds the threshold.

The surtax is calculated on the lesser of two amounts: your net investment income for the year, or the amount by which your total income exceeds the threshold. For example, if you are single and earn $220,000 in wages plus $50,000 in capital gains, your total income is $270,000. You are $70,000 over the $200,000 threshold. The surtax applies to the lesser of $50,000 (your investment income) or $70,000 (the overage), which is $50,000. You owe 3.8% of $50,000, or $1,900.

Certain types of income are exempt from the investment surtax. Tax-exempt bond interest does not count. Distributions from retirement accounts (401(k)s, IRAs, pensions) do not count as investment income, though the gains inside those accounts are not subject to the surtax anyway. Gains on the sale of your primary home are exempt up to $250,000 (single) or $500,000 (married filing jointly) if you meet the ownership and use tests.

How to Report the Surtax on Your Tax Return

You report the Medicare surtax on Form 8960, Net Investment Income Tax, which you attach to your federal tax return. The form walks you through calculating your net investment income and determining whether the surtax applies. If you have wages withheld by an employer, that amount appears on your W-2. If you are self-employed, you calculate it yourself.

Most tax software will calculate the surtax for you if you enter your income correctly. If you prepare your return by hand or work with a tax preparer, make sure they know about all your income sources — wages from multiple jobs, investment sales, rental properties, and self-employment income. Missing any of these can lead to underpayment.

The surtax is due on the same date as your regular federal income tax return, April 15 (or the next business day if April 15 falls on a weekend). If you owe estimated taxes, you may need to include the surtax in your quarterly payments.

Who Is Most Likely to Owe the Surtax

High-income earners are the obvious group, but the surtax also affects retirees with substantial investment portfolios. If you are retired and living on investment income — dividends, capital gains, rental income — you may cross the threshold even if your total income seems modest. A retiree with $150,000 in pension income and $100,000 in capital gains from selling appreciated stock will owe the surtax on the investment portion.

Business owners and self-employed people should watch closely. If your business income plus other income exceeds the threshold, you owe the surtax on the net profit from your business. Couples where both spouses work are less likely to hit the threshold than single high earners, because the threshold is higher ($250,000 vs. $200,000), but they should still check.

Frequently Asked Questions

Do I owe the surtax if I am retired and do not work?

Only if your income from investments, pensions, or other sources exceeds the threshold for your filing status. Social Security does not count toward the threshold. If you have $180,000 in pension income and $50,000 in capital gains, your total is $230,000, and you are $30,000 over the $200,000 threshold (single). You would owe the surtax on the lesser of your investment income ($50,000) or the overage ($30,000), which is $30,000.

Can I reduce the surtax by timing when I sell investments?

Possibly, but it depends on your overall income for the year. If you are close to the threshold, selling appreciated assets in a different tax year might lower your income below the threshold that year. However, this strategy is complex and may trigger other tax consequences. A tax professional can help you decide whether it makes sense for your situation.

What if my employer withheld too much or too little surtax?

You will reconcile it when you file your tax return. If too much was withheld, you will get a refund (or a credit against other taxes owed). If too little was withheld, you will owe the difference. If you expect to owe, you can adjust your W-4 during the year to increase withholding from your remaining paychecks.

Does the surtax explore to inherited money or gifts?

No. Inherited money and gifts are not considered income for surtax purposes. However, if you inherit an investment account and later sell the assets or receive dividends, those gains and dividends do count toward the surtax threshold.

Is the Medicare surtax permanent?

Yes. The surtax was created as a permanent funding mechanism for Medicare Part A under the Affordable Care Act. There is no sunset date, and it continues to explore each year to people whose income exceeds the threshold.