Regular employee Medicare is 1.45% on all covered wages. Additional Medicare Tax is a separate 0.9% on wages above a filing-status threshold. It is not a new Social Security tax. There is no employer match.
The statute is 26 U.S.C. § 3101(b)(2): 0.9 percent of wages in excess of $250,000 on a joint return, half of that ($125,000) if married filing separately, and $200,000 in any other case. Those dollar amounts are not inflation-adjusted.
Run the Additional Medicare calculator →
IRS Topic 751 tells employers to start the extra 0.9% once wages they paid you exceed $200,000 in the calendar year, without looking at your filing status or your spouse’s job. Form 8959 reconciles withholding to the real tax. A joint couple can be over-withheld. Two single-looking jobs can be under-withheld.
Direct answer: statutory tax (not the stub)
threshold = $250,000 (joint) / $125,000 (MFS) / $200,000 (any other case)
excess wages = max(0, calendar-year Medicare wages − threshold)
Additional Medicare Tax = 0.9% × excess wages
| Medicare wages | Status | Threshold | Tax |
|---|---|---|---|
| $180,000 | Single / other | $200,000 | $0 |
| $200,000 | Single / other | $200,000 | $0 |
| $250,000 | Single / other | $200,000 | $450 |
| $250,000 | Joint | $250,000 | $0 |
| $300,000 | Joint | $250,000 | $450 |
| $200,000 | Married filing separately | $125,000 | $675 |
$50,000 over the line × 0.9% = $450. $75,000 over the MFS line × 0.9% = $675. The calculator takes calendar-year Medicare wages and a status. It does not rebuild employer withholding at the flat $200,000 trigger, and it does not compute NIIT 3.8%.
What still shows on a normal paycheck
Until you cross $200,000 of wages at that employer, the extra 0.9% usually does not appear. Regular Medicare stays 1.45%. Social Security stays 6.2% until the $184,500 2026 wage base. Those two lines are the FICA calculator.
On a mid-year $2,000 biweekly check with no Additional Medicare, employee FICA is still $153.00. That is the paycheck default: $124.00 Social Security + $29.00 Medicare. The 0.9% is a third Medicare-related line, and only on the excess.
Each employer looks at its $200,000. Two $150,000 W-2s may withhold zero extra 0.9%, while a single or MFS return owes tax on wages above $200,000 or $125,000. That gap is why Form 8959 exists. Extra W-4 Step 4(c) dollars can cover it. They do not compute this tax. See W-4 Step 4.
Self-employment is a cousin, not this page
SECA Medicare is 2.9% on 92.35% of net earnings (Topic 554). Additional Medicare can also apply to self-employment income at the same dollar thresholds, through a different form path. The take-home engine on this site excludes that 0.9% on purpose. High earners should not treat $39,539.11 on $50,000 as a high-income template.
NIIT (3.8% on certain net investment income) is a third rule. Do not add 0.9% + 3.8% on the same wage dollars and call it “Medicare.”
What this page is not
- Not the 1.45% Medicare line. That is ordinary FICA.
- Not a 50-state hospital tax.
- Not tax advice, and not Form 8959 filled in for you.
No. Once you are over the threshold, 0.9% applies to the excess. There is no $184,500 cap on this slice.
The tax threshold for a joint return is $250,000. Withholding can still start at $200,000 on one job. The extra withheld is a credit against the return, not extra tax by itself. Confirm on Form 8959.
No. Topic 751 and § 3101(b)(2) describe an employee tax. The employer 1.45% match does not grow by 0.9%.
Only if you are also near the $184,500 Social Security wage base. That cap and this 0.9% threshold are independent. Run FICA for the 6.2% / 1.45% piece and this calculator for the excess 0.9%.