What Is IRMAA?

IRMAA stands for Income-Related Monthly Adjustment Amount — an extra amount some people pay on top of their standard Medicare Part B and Part D premiums, based on income.

How Income Is Measured

Social Security determines whether IRMAA applies using your modified adjusted gross income from your tax return two years prior. For example, income reported for 2024 would generally be used to determine IRMAA for 2026.

It's Based on Brackets

IRMAA is applied in income brackets — the higher your reported income, the higher the surcharge tier. These brackets and dollar amounts are set by the federal government and typically adjust each year, so it's worth confirming the current figures rather than relying on last year's numbers.

You Can Appeal It

If your income has dropped since the tax year used to calculate your IRMAA — due to retirement, a life-changing event, or another qualifying reason — you can generally request that Social Security use more recent income information instead.

IRMAA catches a lot of people by surprise. Written by Rafael Stella, a licensed Medicare insurance agent helping people throughout California understand their coverage costs at no cost — see the About page to learn more, or reach out with questions about your specific situation.