Additional Medicare Tax Calculator (0.9%)

Enter your wages, self-employment income, and filing status to calculate your 0.9% Additional Medicare Tax liability and total Medicare burden.

Created by Luis GonzalezLast updated: 2026-06-07

How to Use This Calculator

1
Enter Income and Filing Status
Input your W-2 Wages / Compensation, Self-Employment Net Income, and select your Filing Status (Single, MFJ, MFS, or Head of Household). The filing status determines your income threshold.
2
Review Your Results
The calculator displays Additional Medicare Tax, Income Subject to 0.9% Tax, Regular Medicare Tax (1.45%), and Total Medicare Tax. The Medicare Tax Insights panel shows your filing status threshold, total income assessed, effective combined rate, and self-employment share, plus a Medicare Tax Composition breakdown bar.

Example Calculation

A single taxpayer earns $200,000 in W-2 wages and $50,000 in self-employment income, needing to calculate their Additional Medicare Tax liability.

W-2 Wages / Compensation

$200,000

Self-Employment Net Income

$50,000

Filing Status

Single

Results

Additional Tax

$450.00

Subject to 0.9%

$50,000

Regular Tax

$3,625.00

Total

$4,075.00

Tips

Threshold Varies by Filing Status

The 0.9% tax kicks in at $200,000 for Single/HoH, $250,000 for MFJ, and $125,000 for MFS. A married couple each earning $180,000 would owe no additional tax filing jointly ($360,000 - $250,000 = $110,000 subject), but filing separately each would owe ($180,000 - $125,000 = $55,000 subject per spouse).

Plan Estimated Payments for Self-Employment Income

Employers withhold the additional 0.9% once W-2 wages exceed $200,000, but self-employment income is not subject to withholding. If SE income pushes you over the threshold, make quarterly estimated payments to avoid underpayment penalties.

Both Income Sources Count Together

The threshold applies to combined wages + self-employment income. $150,000 in wages alone wouldn't trigger the tax for a single filer, but adding $60,000 in SE income pushes total income to $210,000 — putting $10,000 subject to the additional 0.9% ($90 in extra tax).

Calculate Your 0.9% Additional Medicare Tax

The Additional Medicare Tax Calculator determines liability for the 0.9% Medicare surtax on high earners.

For a single filer with $200,000 in W-2 wages and $50,000 in self-employment income: additional Medicare tax is $450.00 on $50,000 above the $200,000 threshold, regular Medicare tax is $3,625.00 (1.45% of $250,000), and total Medicare tax is $4,075.00 at an effective combined rate of 1.630%.

The Medicare Tax Insights panel shows filing status threshold, total income breakdown, and effective rate context.

The Additional Medicare Tax Formula

The calculation layers the 0.9% surtax on top of the standard 1.45% Medicare tax:

totalIncome          = wages + selfEmploymentIncome
incomeSubjectToTax   = max(0, totalIncome - filingStatusThreshold)
additionalMedicareTax = incomeSubjectToTax x 0.009
regularMedicareTax   = totalIncome x 0.0145
totalMedicareTax     = regularMedicareTax + additionalMedicareTax
effectiveRate        = totalMedicareTax / totalIncome x 100

Filing status thresholds: Single / HoH = $200,000; MFJ = $250,000; MFS = $125,000.

Additional metrics — filing threshold, total income assessed, effective rate, and self-employment share — appear in the Medicare Tax Insights panel.

💡 For a broader view of your tax obligations, including potential refunds or liabilities, our Tax Refund Estimator can provide a comprehensive outlook.

A Single Filer with $250,000 in Combined Income

A single taxpayer earns $200,000 in W-2 wages and $50,000 in net self-employment income in 2026.

Total Income: $200,000 + $50,000 = $250,000.
Filing Threshold (Single): $200,000 — income above this is subject to the 0.9% surtax.
Income Subject to 0.9% Tax: $250,000 - $200,000 = $50,000 (20.0% of total income).
Additional Medicare Tax: $50,000 x 0.9% = $450.00.
Regular Medicare Tax: $250,000 x 1.45% = $3,625.00.
Total Medicare Tax: $3,625.00 + $450.00 = $4,075.00 — effective combined rate of 1.630%.

The Medicare Tax Insights panel also shows: filing status threshold of $200,000 (Single), total income of $250,000 ($50,000 above threshold), effective combined rate of 1.630%, and self-employment share of $50,000 (20.0% of total income).

The Tax Composition bar shows regular Medicare ($3,625) vs. additional Medicare ($450).

💡 To understand how different income levels and deductions affect your overall tax burden, explore our Tax Multiplier Calculator.

Withholding and Estimated Payment Considerations

Employers must withhold the additional 0.9% once W-2 wages exceed $200,000, regardless of filing status.

This creates a mismatch for MFJ filers: each spouse's employer uses the $200,000 threshold for withholding, but the actual threshold is $250,000 on the joint return.

A couple where each spouse earns $190,000 would have no withholding (neither exceeds $200,000), but their $380,000 combined income generates $130,000 subject to the additional tax ($1,170 owed).

Conversely, MFS filers with the $125,000 threshold may have too much withheld by employers using the $200,000 trigger.

In both cases, adjusting W-4 withholding or making quarterly estimated payments prevents surprises at filing time.

Strategies for Managing the Additional Medicare Tax

Maximizing pre-tax retirement contributions (401(k), traditional IRA) reduces W-2 wages and can keep income below thresholds.

For self-employed individuals, legitimate business expense deductions reduce net SE income.

However, the thresholds are not indexed for inflation — they've been unchanged since 2013.

With cumulative inflation exceeding 30% since then, the tax affects significantly more taxpayers each year than originally intended.

A $200,000 salary in 2013 would need to be roughly $265,000 in 2026 to maintain the same purchasing power, meaning the real threshold has effectively dropped.

Frequently Asked Questions

What is the 0.9% Additional Medicare Tax?

The 0.9% Additional Medicare Tax is a surtax on earned income above certain thresholds, introduced by the Affordable Care Act (ACA). It applies to wages, compensation, and self-employment income exceeding $200,000 for single filers or $250,000 for MFJ. This tax is in addition to the standard 1.45% Medicare tax, and is solely the employee's responsibility — employers don't match it.

Who is subject to the Additional Medicare Tax?

Individuals whose combined wages and net self-employment income exceed their filing status threshold: $200,000 (Single/HoH), $250,000 (MFJ), or $125,000 (MFS). Only income above the threshold is taxed at the additional 0.9%. For the default scenario, $50,000 of the $250,000 total income exceeds the $200,000 single threshold.

How does this differ from the regular Medicare tax?

The regular Medicare tax (1.45% employee / 1.45% employer) applies to all earned income with no cap. The additional 0.9% applies only to income above the threshold and is paid entirely by the employee. In the default scenario: regular tax is $3,625.00 (1.45% of $250,000) and the additional tax is $450.00 (0.9% of $50,000), for a total of $4,075.00.

Does this tax apply to investment income?

No. The 0.9% Additional Medicare Tax applies only to earned income (wages and self-employment). Investment income like capital gains, dividends, and interest may be subject to the separate 3.8% Net Investment Income Tax (NIIT) if MAGI exceeds similar thresholds. These are two distinct taxes.

Are these thresholds indexed for inflation?

No. The Additional Medicare Tax thresholds ($200,000/$250,000/$125,000) have remained unchanged since the tax was introduced in 2013 and are not indexed for inflation. As wages grow with inflation, more taxpayers cross these thresholds each year — a phenomenon known as bracket creep.