Medicare Surtax Calculator
Find out in 30 seconds if you owe the Medicare surtax, and why your job did not take it out. Any year from 2019 to 2025. Free, no account, we store nothing.
Your W-2s
Boxes 1, 5 and 6 are on the W-2. One row per job. Box 1 is often lower than box 5 if you put money in a 401(k).
“Medicare surtax” means three things
The 0.9% on pay
Form 8959. It starts once your pay and self-employment income pass the threshold for your filing status. This page does that math.
The 3.8% on investments
Form 8960. Interest, dividends, gains and rent, once your total income passes the same threshold. This page does that math too.
The Medicare premium surcharge (IRMAA)
That one is a higher Part B or Part D premium. Social Security sets it from your income two years back. It is not a tax form. We do not do that one here.
Why this happens
Your job only looks at your job
An employer takes out the 0.9% once your pay there passes $200,000. It does not know about your spouse's job or your second job. So two people who each make $150,000 owe it, and nobody took it out.
One big job, married: you get money back
If one job paid over $200,000 but you file jointly and stay under $250,000, your employer took out tax you do not owe. The form gives it back on your return.
Married filing separately has a low threshold
It is $125,000, half the joint one. Filing apart can turn a $0 answer into a bill.
Self-employment counts too
Your net profit, after the 92.35% step on Schedule SE, is added to your pay. The 0.9% is extra. It is not part of your self-employment tax.
The 3.8% starts with your first big sale
Sell stock or a rental in a good year, and your total income can jump past the line. The 3.8% is on the smaller of your investment income or the amount over the line.
How to stop it next year
Give your employer a new W-4. Put the extra you expect to owe on Step 4(c), spread over your paychecks. Or send estimated payments.
How to use it
- 1Pick the year and how you file. Married filing jointly has a higher threshold than single.
- 2Type box 5 and box 6 from each W-2. Or drop the W-2s and we read them.
- 3Add self-employment profit if you have it. Open the 3.8% part if you have investments.
- 4Tap Show my answer. Read the three lines, then check the filled forms.
Every year, 2019 to 2025
The thresholds are the same every year. What changes is the due date, the refund window and where the tax goes on Schedule 2.
Medicare surtax 2025
The return you file in 2026. If you owe the surtax, it goes on Schedule 2. If your job took out too much, you get it back. A new W-4 now gets 2026 right.
Medicare surtax 2024
Due in April 2025. If you are doing it now, you are late or fixing it. Filing still gets back what your job took out too much of, until April 2028.
Medicare surtax 2023
Due in April 2024. You can still claim a refund until April 15, 2027. If one big job took out the 0.9% and you file jointly under $250,000, that money is yours.
Medicare surtax 2022
Due in April 2023. The refund window closed April 15, 2026. If you owe, the IRS can still bill you. Use this page to check their number. If it is wrong, answer the notice with Form 8959 filled in.
Medicare surtax 2021
Due in April 2022. The first year Schedule 2 gave each tax its own line, 11 and 12. The refund window closed April 15, 2025. A balance can still be billed.
Medicare surtax 2020
Due May 17, 2021, pushed back for COVID. Both taxes went on Schedule 2, line 8, with a box to check for each form. The refund window closed May 17, 2024.
Medicare surtax 2019
Due July 15, 2020, pushed back for COVID. Both taxes went on Schedule 2, line 8. The refund window closed July 17, 2023. If you get a notice for 2019, this page checks their number.
Questions people ask
Yes. Type your numbers or drop your W-2s. No account, no email, no trial.
No. The math runs on our server and comes right back. We keep no copy. Close the tab and it is gone.
Yes. It is the same tax engine that builds our returns. The lines you see are Form 8959 and Form 8960 as the engine fills them.
It is two taxes. One is the 0.9% Additional Medicare Tax. It is on pay and self-employment income over a set threshold. The other is the 3.8% Net Investment Income Tax. It is on interest, dividends, gains and rent, once your total income passes that threshold. People call both the Medicare surtax.
Your employer only looks at your pay from them. The 0.9% starts at $200,000 at one job, no matter how you file. If two jobs or two spouses each stay under that, nobody takes it out, but you may still owe it.
No. The calculator asks for dollar amounts and how you file. If you drop a W-2, we read boxes 1, 5 and 6 and keep no copy of the file.
No. They have been $200,000 single, $250,000 married filing jointly and $125,000 married filing separately every year since 2013. What changed is where the tax goes on Schedule 2, and which refund windows are still open. The table below has every year.
Guides for Medicare surtax filers
W-2
What is the Additional Medicare Tax, and why do I owe it?
It's 0.9% on wages over $200,000, and if you're married, your employer may never have withheld it. Who owes it, how much, and how to stop the surprise.
Read article
W-2
Net investment income tax: the 3.8% nobody warned you about
Sell stock in a good year and a 3.8% tax can appear on top of capital gains. Who owes it, what counts, and a worked example in real dollars.
Read article
W-2
Why do I owe taxes? I'm a W-2 employee
Your employer withheld all year and you still owe. Usually it's your bonus, your RSUs, or two incomes. Here's which one, what it costs, and how to stop it next year.
Read articleLink to this tool
Sharing it with a client, a bookkeeper or a forum? Copy the line below.
Medicare Surtax Calculator, free: https://cofiled.com/medicare-surtax-calculator