Additional Medicare Tax is an extra 0.9% tax on wages and self-employment income above a set threshold. Your employer must start withholding it once your wages from that job pass $200,000 in a calendar year, and there is no employer match.
The withholding rule and the actual tax rule are not the same, and that gap is where most surprises come from. Withholding is based on what one employer pays you. The tax you owe is based on your total earnings and your filing status. This guide explains both and shows how to tell whether you will owe more when you file.
How Additional Medicare Tax Works
Regular Medicare tax is 1.45% of all your wages, with no cap. Additional Medicare Tax adds 0.9% on top, but only on the portion of earnings above your threshold. So above that line, the employee share of Medicare becomes 2.35% instead of 1.45%.
A few points set it apart from regular Medicare tax:
- Employee only. Your employer pays 1.45% on all your wages but pays nothing extra on the 0.9%.
- Threshold depends on filing status when you file your return, even though employers use a single $200,000 trigger for withholding.
- It counts all your Medicare wages from every job, plus self-employment income, when you figure what you owe.
Additional Medicare Tax Thresholds by Filing Status
For 2026, these are the amounts above which the 0.9% tax applies on your return:
| Filing status | Threshold for the tax you owe | Employer withholding trigger |
|---|---|---|
| Single | $200,000 | $200,000 from one employer |
| Head of household | $200,000 | $200,000 from one employer |
| Married filing jointly | $250,000 (combined) | $200,000 from one employer |
| Married filing separately | $125,000 | $200,000 from one employer |
Your employer does not know your filing status for this purpose or what your spouse earns, so it uses $200,000 for everyone. You cannot ask your employer to stop withholding once you pass $200,000, even if you expect to owe less. If your situation means you will owe more, you can cover it with extra withholding on your W-4 or with estimated tax payments.
Worked Example: A $240,000 Salary in Washington
Say you earn $240,000, are paid biweekly, file single, and live in Washington. Each paycheck is $9,230.77 gross. Here is how Medicare withholding actually moves through the year:
| Paychecks | Medicare withheld per paycheck | What is happening |
|---|---|---|
| 1 through 21 | $133.85 | Regular 1.45% only; year-to-date wages reach $193,846.17 |
| 22 | $161.54 | Wages cross $200,000; 0.9% applies to the $3,076.94 above it |
| 23 through 26 | $216.92 | Full 2.35% on every dollar |
Total Medicare tax for the year comes to about $3,840: $3,480 of regular Medicare plus $360 of Additional Medicare Tax on the $40,000 above the threshold. The PaycheckHubs paycheck calculator shows the same annual total but spreads it evenly, at $147.69 per paycheck, so your real stubs will look lower early in the year and higher at the end.
For this single filer with one job, the withholding and the tax owed match, so nothing extra is due at filing for Medicare.
When You Can Owe More Than Was Withheld
Married couples with two incomes
Picture a married couple where each spouse earns $150,000. Neither employer ever reaches $200,000, so neither withholds any Additional Medicare Tax. Each spouse has about $2,175 of regular Medicare withheld for the year.
But they file jointly with $300,000 of combined wages, which is $50,000 over the $250,000 married threshold. They owe 0.9% of $50,000, or $450, when they file. That amount is not a penalty for anything done wrong; it was simply never withheld because no single paycheck triggered it.
Two or more jobs
If you are single and earn $130,000 at one job and $90,000 at another, neither employer passes $200,000. Your combined $220,000 is still $20,000 over your threshold, so you would owe 0.9% on that amount at filing.
Wages plus self-employment income
Self-employment earnings also count toward the threshold, and self-employed people pay the 0.9% on net earnings above it. If you have a salaried job and a side business, the two can combine to push you over even when your paycheck alone does not. See how side hustle income is taxed for the bigger picture.
When You May Get Some of It Back
The reverse can happen too. A married couple where one spouse earns $220,000 and the other earns nothing will have Additional Medicare Tax withheld on $20,000 of wages. Their joint threshold is $250,000, so they owe none. The amount withheld is credited against their total tax when they file.
The calculation on your return is done on Form 8959, which compares what you owe with what employers withheld.
How to Plan for It
- Add your expected Medicare wages from every job, plus any self-employment income, and compare the total with the threshold for your filing status.
- If you expect to owe, you can add a dollar amount per paycheck in Step 4(c) of your W-4. Our guide on filling out a W-4 with two jobs or a working spouse covers how that step works.
- Use the IRS Tax Withholding Estimator to check your total federal withholding, including this tax.
- For a personal situation with several income sources, a tax professional can confirm what you owe.
Additional Medicare Tax is federal, so it works the same in every state, from Washington to Colorado. Only your state income tax changes.
Frequently Asked Questions
What is the Additional Medicare Tax rate?
It is 0.9% on wages and self-employment income above your threshold. Combined with regular Medicare, the employee share becomes 2.35% on earnings over the line.
Does my employer pay Additional Medicare Tax too?
No. Employers match the regular 1.45% Medicare tax but pay nothing toward the 0.9% additional tax.
Why didn't my employer withhold Additional Medicare Tax?
Employers only withhold it once the wages they pay you pass $200,000 in a calendar year. Combined income from two jobs or a spouse's job is not considered, so you may owe it at filing instead.
Can I ask my employer to stop withholding it?
No. Once your wages from that employer pass $200,000, the employer must withhold it. Any excess is credited when you file your return.
Sources
- IRS Topic No. 560, Additional Medicare Tax
- IRS Publication 15, Employer's Tax Guide
- IRS: Self-Employment Tax (Social Security and Medicare Taxes)
Run the numbers for your state
Written and checked against IRS, Social Security Administration and state tax agency publications for the 2026 tax year. General information, not tax, legal or financial advice. Read our editorial policy, calculation methodology and sources.