One-Time Income and IRMAA: How a Home Sale or Roth Conversion Can Spike Your Medicare Premiums

Many people first learn about IRMAA the hard way, when their Medicare premiums jump two years after an unusually good financial year. IRMAA, the Income-Related Monthly Adjustment Amount, is a surcharge on Part B and Part D premiums for higher-income beneficiaries, and it is calculated from your tax return two years in the past. That two-year lag means a single one-time income event, like selling a home or converting a large sum to a Roth, can raise your Medicare costs long after the money is spent. The most important thing to understand is that many of these events cannot be appealed, so the planning has to happen before, not after.

Bryce's Take

The clients who get blindsided by IRMAA are usually the ones who had a great financial year and did not connect it to Medicare. They sold the lake house or did a big Roth conversion, and two years later their premium jumps and they call me furious, wanting to appeal. The hard truth is that a home sale and a Roth conversion do not qualify for an appeal. That is exactly why this planning has to happen before the event, in coordination with whoever handles your taxes, not after the surcharge letter arrives.

How IRMAA is calculated

IRMAA is based on your modified adjusted gross income, or MAGI, from your tax return two years earlier. So your 2025 Medicare premiums are determined by your 2023 income. If your MAGI that year exceeded the first IRMAA threshold, you pay a surcharge on top of the standard Part B premium and an additional amount on your Part D premium. The surcharge climbs in tiers, so the higher your income above the first threshold, the larger the monthly add-on. Social Security notifies you of the adjustment, usually catching people off guard because the triggering year feels like ancient history by then.

The one-time income events that trip people up

The events most likely to push a normally moderate-income retiree over an IRMAA threshold are almost always one-time. Selling a home can generate capital gains above the exclusion amount. A large Roth conversion adds the converted amount to your taxable income for that year. Required minimum distributions, exercising stock options, an inheritance that produces taxable income, or the sale of a business can all do the same. None of these reflect your ongoing income, but IRMAA does not care. It looks at that single year's MAGI and adjusts accordingly.

The two-year lag cuts both ways

The lag that blindsides people also works in your favor. Because IRMAA is set from income two years back, a surcharge triggered by a one-time event in a single year lasts only for the year or years that reflect it. Once your income returns to normal, the surcharge falls away two years later. So a home sale in one year may raise your premiums for a single year down the road, then reset. IRMAA is recalculated annually against the relevant prior-year return, so it is not permanent the way a late-enrollment penalty is.

Why you usually cannot appeal a home sale or Roth conversion

This is the nuance that catches even well-informed retirees. You can appeal IRMAA using Social Security Form SSA-44, but only for a qualifying life-changing event. The qualifying events are specific: marriage, divorce, death of a spouse, work stoppage or reduction, loss of income-producing property due to a disaster, and a few others. A home sale is not a qualifying life-changing event. A Roth conversion is not either. Because these are voluntary financial decisions rather than the defined life-changing events, you generally cannot appeal the resulting surcharge. The premium increase stands.

When SSA-44 actually helps

Form SSA-44 is genuinely useful when a real life-changing event has reduced your income below what your two-year-old return shows. The classic case is retirement: if you stopped working and your current income is far lower than the year Social Security is using, you can file SSA-44 to have IRMAA recalculated on your reduced income. The lesson is to know the difference. If your income dropped because of a qualifying event, appeal. If it spiked because of a home sale or conversion you chose, the appeal door is closed, so the answer is planning.

Planning around the thresholds

Because you cannot appeal a voluntary income event, the strategy is to manage the event before it happens. Roth conversions can be spread across several years to keep any single year under a threshold. A home sale can be timed, and the capital gains exclusion for a primary residence can shelter a large portion of the gain for many sellers. Watching where your MAGI lands relative to the next IRMAA bracket, and coordinating conversions, distributions, and sales with that in mind, can keep a good financial year from quietly raising your Medicare premiums two years later.

Bryce Casson

Licensed Independent Medicare Broker

Bryce Casson is an independent Medicare insurance broker who works with every major carrier. He does not represent any single insurer, which means his recommendations are based on what actually fits each client's situation, not on commissions or quotas.