1. Tax Rate. The Additional Medicare Tax rate is 0.9 percent.
2. Income Subject to Tax. The tax applies to the amount of certain income that is more than a threshold amount. The types of income include your Medicare wages, self-employment income and railroad retirement (RRTA) compensation. See the instructions for Form 8959, Additional Medicare Tax, for more on these rules.
3. Threshold Amount. You base your threshold amount on your filing status. If you are married and file a joint return, you must combine your spouse’s wages, compensation or self-employment income with yours. Use the combined total to determine if your income exceeds your threshold. The threshold amounts are:
- Married filing jointly: $250,000
- Married filing separately: $125,000
- Single: $200,000
- Head of household: $200,000
3. Withholding/Estimated Tax. Employers must withhold this tax from your wages or compensation when they pay you more than $200,000 in a calendar year. If you are self-employed you should include this tax when you figure your estimated tax liability.
4. Underpayment of Estimated Tax. If you had too little tax withheld, or did not pay enough estimated tax, you may owe an estimated tax penalty. For more on this, please call.
5. Form 8959. If you owe this tax, file Form 8959, Additional Medicare Tax, with your tax return. You also report any Additional Medicare Tax withheld by your employer on Form 8959.
If you have any questions about the Additional Medicare Tax, help is just a phone call away.