IRMAA stands for Income-Related Monthly Adjustment Amount. It’s an additional surcharge added to Medicare Part B (and typically Part D) premiums when your income exceeds certain IRS thresholds. The ongoing issue is that IRMAA is generally based on your reported income from prior years, so premium increases can feel delayed, unexpected, and disconnected from your current cash flow—especially after one-time income events like large IRA distributions, capital gains, or a Roth conversion. Once triggered, IRMAA can raise monthly Medicare costs for an entire year (or longer if higher income continues), and because it’s structured in income “tiers,” a relatively small increase in income can sometimes move you into a higher bracket—creating a meaningful jump in premiums that becomes a recurring drag for years Retiremenon retirement income and budgeting.
