IRMAA Explained: How It Can Impact Medicare Premiums
For many retirees, Medicare can seem like a fixed cost. You enroll, you pay the standard premium, and that's largely that.
But for high-income earners, Medicare comes with a surcharge that can add hundreds of dollars per month to that bill, and the income that triggers it may have been earned two years earlier. Understanding the Income-Related Monthly Adjustment Amount, commonly known as IRMAA, is an important part of retirement income planning for anyone who has built significant wealth.
What Is IRMAA?
The Income-Related Monthly Adjustment Amount (IRMAA) is a surcharge applied to Medicare Part B and Part D premiums for beneficiaries whose income exceeds certain thresholds. It is not a penalty in the traditional sense. It is simply a tiered premium structure in which higher-income beneficiaries pay more for the same coverage. The surcharge is calculated based on your modified adjusted gross income, or MAGI, from two years prior to the current Medicare year.
The Social Security Administration generally uses your tax return from two years prior when setting IRMAA. If that return is not available, SSA may use the most recent return it has, which can sometimes be from three years prior. In practical terms, this means your Medicare costs in retirement can be shaped by income decisions you make years before you ever enroll.
For 2026, the IRMAA surcharge applies to single filers with MAGI above $109,000 and to married couples filing jointly with MAGI above $218,000. Married couples filing separately are subject to different, more compressed thresholds, so filing status can meaningfully affect IRMAA exposure.
The surcharges increase across five MAGI tiers, with the highest bracket applying to individuals with MAGI of $500,000 or more and married couples filing jointly with MAGI of $750,000 or more. At the top tier, the combined Part B and Part D surcharge can add over $6,900 per year in additional premiums for an individual, and more than $13,800 for a couple.
What Counts as Income for IRMAA Purposes?
This is where IRMAA surprises many people who believe they have planned carefully. IRMAA MAGI is calculated as your adjusted gross income plus any tax-exempt interest income. That definition is broader than most people expect.
The following income sources can all count toward your IRMAA calculation:
- Traditional IRA and 401(k) distributions, including required minimum distributions
- The taxable portion of Social Security benefits
- Capital gains from the sale of investments, real estate, or other assets
- Pension income and annuity payments
- Interest and ordinary dividends from taxable accounts
- The amount converted in a Roth conversion
- Tax-exempt interest from municipal bonds
That last item catches even sophisticated investors off guard. Municipal bond interest is excluded from federal income tax but added back to MAGI for IRMAA purposes. A retiree who holds a significant municipal bond portfolio may find themselves in a higher IRMAA bracket despite having little taxable income in the conventional sense.
Why the Two-Year Lookback Matters for Planning
The mechanics of IRMAA create a planning window that most people do not take full advantage of. Because the surcharge is based on income from two years prior, the years just before Medicare enrollment, typically ages 63 and 64 for someone enrolling at 65, are often the most consequential. Income decisions made during those years can determine your premium tier for the first year of Medicare coverage.
This is not just a Medicare issue. It is a sequencing problem that intersects with some of the most significant financial decisions in early retirement:
- When to start Social Security
- How aggressively to draw down pre-tax accounts
- Whether to execute Roth conversions
- How to time large capital gain events like the sale of a business or investment property
Each of those decisions affects MAGI, and MAGI affects Medicare premiums with a two-year delay. Thoughtful retirement planning takes that delay into account. A Roth conversion that makes sense in isolation may, for example, push MAGI above an IRMAA threshold in the conversion year, resulting in higher Medicare premiums two years later. That tradeoff may still be worth making. But it should be a deliberate choice, not an unintended consequence.
Strategies Worth Considering
Managing IRMAA exposure is not about avoiding income. It is about sequencing income thoughtfully and using the right accounts at the right times. A few approaches are worth understanding.
Roth conversions in lower-income years.
The years between retirement and the start of Social Security or RMDs can represent a window of relatively low taxable income. Converting pre-tax IRA or 401(k) balances to Roth during this window increases income in the conversion year, but reduces future RMDs and future MAGI. Spreading conversions across multiple years, rather than doing one large conversion, can keep each year's MAGI below the next IRMAA threshold. For more on how income coordination works in retirement, explore Quotient's tax strategy and preparation overview.
Qualified charitable distributions.
For retirees age 70½ and older who give to charity, a qualified charitable distribution, or QCD, allows you to transfer up to $111,000 directly from a traditional IRA to an eligible charity in 2026. The QCD can satisfy all or part of your RMD for the year if completed properly as a direct transfer from your IRA to an eligible charity. Because a qualifying QCD is excluded from AGI, it also stays out of MAGI for IRMAA purposes. Unlike a standard cash gift, you do not claim the QCD as an itemized charitable deduction.
Coordinating Social Security timing.
Delaying Social Security can create years in which benefits have not yet begun, potentially reducing MAGI and creating space for Roth conversions or other income-generating moves without triggering higher IRMAA tiers. The interaction between Social Security timing and IRMAA is one reason this decision warrants more analysis than most people give it.
Managing capital gain events.
Large, one-time income events, such as selling a business, liquidating a concentrated stock position, or selling a second home, can push MAGI into a higher IRMAA bracket for a single year. In some cases, it makes sense to accelerate other taxable income into the same high-income year rather than spreading it across multiple years and sustaining an elevated IRMAA surcharge for a longer period. In other cases, the better path is deferral or installment structuring. The right answer depends on your full financial picture.
IRMAA Is Recalculated Every Year
One important nuance: IRMAA is not permanent. Premiums are recalculated annually based on the income from the applicable lookback year. If your income spikes in one year due to a large capital gain or Roth conversion, your Medicare premium two years later may reflect that. But if income returns to a lower level in the following year, the surcharge adjusts accordingly.
This also means that a single high-income year does not permanently lock you into elevated premiums. It is another reason why managing income year by year, rather than optimizing a single year in isolation, tends to produce better outcomes over time.
It is also worth knowing that if your income drops significantly due to a qualifying life-changing event, such as retirement, divorce, or the death of a spouse, you can request that the Social Security Administration use more recent income data rather than the two-year lookback figure. This appeal process will not eliminate the surcharge in every case, but it can provide relief when circumstances have materially changed.
Frequently Asked Questions About IRMAA
How is the Medicare premium calculated?
Your Medicare Part B premium is calculated by adding the standard base premium to any applicable IRMAA surcharge. For 2026, the standard Part B premium is $202.90 per month, and the annual Part B deductible is $283. If your MAGI from two years prior exceeds the lowest IRMAA threshold ($109,000 for single filers, $218,000 for joint filers), a surcharge is added on top of that base amount. The surcharge increases across five income tiers. Part D premiums work the same way: a base premium specific to your plan is increased by an IRMAA surcharge if your income exceeds the applicable threshold.
Does a Roth conversion trigger IRMAA?
Yes. The amount converted from a traditional IRA or 401(k) to a Roth account is treated as ordinary income in the year of the conversion, and it counts toward your MAGI for IRMAA purposes. This does not mean Roth conversions should be avoided. It means they should be sized and timed with IRMAA thresholds in mind, particularly in the years just before Medicare enrollment. A well-structured conversion strategy can reduce long-term IRMAA exposure even if individual conversion years carry a temporary surcharge.
What if my income has dropped since the lookback year?
If your income has declined significantly due to a qualifying life-changing event, you can file an appeal with the Social Security Administration using Form SSA-44. Qualifying events include retirement or reduction in work hours, marriage or divorce, and the death of a spouse, among others. If approved, the SSA will use income from a more recent year to calculate your premium rather than the standard two-year lookback figure.
For high-income professionals approaching retirement, IRMAA is one of those details that can feel minor until it isn't. A few thousand dollars per year in potential surcharges can add up across a long retirement. In some cases, paying IRMAA may still be worth it, but it should be part of a deliberate planning decision. More importantly, the income decisions that drive IRMAA exposure are the same ones that drive tax efficiency, Social Security optimization, and long-term account balance management. Getting those decisions right requires looking at them together, not in isolation. That coordination is exactly what a Quotient advisor is here to provide. Schedule a consultation with a Quotient financial advisor today.
