Additional Medicare Tax — Payroll Definition

What is Additional Medicare Tax?

Additional Medicare Tax is an employee-only 0.9% tax on Medicare wages, railroad retirement compensation, and self-employment income above the applicable filing-status threshold. Employers begin withholding after paying an employee more than $200,000 in a calendar year, without considering filing status or wages from another employer. The final tax can therefore differ from the amount withheld and is reconciled on the individual return.

How to apply this payroll definition

Locate the label beside its current-period amount, taxable-wage basis, and year-to-date total. Compare it with prior genuine statements, benefits materials, the employer's payroll documentation, and the primary source linked on this page. The same abbreviation can carry a different employer-specific meaning.

What the label does not prove

A familiar term or plausible amount does not authenticate a pay statement or confirm identity, employment, wages, deductions, tax compliance, or eligibility. Ask the verified payroll contact about an unknown code. Use current agency instructions or a qualified adviser when a rate, filing, benefit, garnishment, or legal decision depends on the answer.

Browse all payroll definitions or use the pay-statement codes guide.