IRMAA Calculator

What IRMAA actually is

The Income-Related Monthly Adjustment Amount is a per-person surcharge that higher-income beneficiaries pay on top of the standard Medicare Part B and Part D premiums. It applies to both spouses if both are on Medicare, which is why a couple crossing a tier line often sees the surcharge felt twice. IRMAA does not change benefits. It changes what those benefits cost each month.

The two-year lookback

IRMAA is not based on the current year of income. It uses the Modified Adjusted Gross Income from the tax return two years prior. For 2025 IRMAA, the relevant number is 2023 MAGI. This is why proactive planning matters. By the time a client sees the surcharge on their premium notice, the income event that caused it is already two years in the rear-view mirror and cannot be undone.

MAGI is broader than taxable income

The MAGI used for IRMAA is generally Adjusted Gross Income plus tax-exempt interest. That means municipal bond interest, which is usually federally tax-free, still counts here. Roth conversion amounts count. Large realized capital gains count. Taxable Required Minimum Distributions count. Regular Roth withdrawals and Health Savings Account withdrawals for qualified medical expenses do not.

The cliff structure, and why it stings

IRMAA is not phased in gradually. Cross a threshold by one dollar and the higher surcharge applies to the entire year, on both spouses. That structural cliff is the reason careful planners model MAGI to a target, not to a range. It is common to see a large year-end capital gain or an overly aggressive Roth conversion trigger four figures of additional annual premium the client did not budget for.

Appeals and life-change events

The Social Security Administration accepts appeals when a qualifying life event has changed the client's income picture. Retirement itself is on that list. Marriage, divorce, death of a spouse, and the loss of an income-producing property or pension all qualify. The appeal form is SSA-44 and it requires documentation. It is worth pursuing anytime a client's current income is materially lower than the return SSA is using.

Planning levers that actually help

The playbook is small and consistent. Space Roth conversions across years to keep MAGI just under the next cliff. Use Qualified Charitable Distributions after age 70½ to satisfy some of the RMD without adding to MAGI. Harvest capital losses in years where a surcharge is close. Coordinate the sale of a business or a piece of real estate to avoid stacking income in a Medicare year. None of it is exotic. It just requires looking two years ahead.