Question 1

What is IRMAA?

Accepted Answer

IRMAA stands for Income-Related Monthly Adjustment Amount. It is the Medicare premium surcharge that applies to Part B (outpatient medical coverage) and Part D (prescription drug coverage) for beneficiaries whose income exceeds a baseline threshold. Most Medicare beneficiaries pay the standard Part B premium — $185.00 per month in 2026. If your income is above the Tier 1 threshold, you pay the standard premium plus an IRMAA surcharge. The surcharge scales across five tiers, reaching its highest level for beneficiaries with MAGI above $500,000 for single filers or $750,000 for married-filing-jointly. The Social Security Administration (SSA) administers IRMAA and uses your income tax data from the IRS to determine the adjustment. IRMAA is not a penalty — it is a premium adjustment built into the Medicare program structure under the Medicare Modernization Act and governed by 42 CFR §408.2. For retirement-income planning, IRMAA is a material cost: a household where both spouses are on Medicare and both are in the highest IRMAA tier could pay roughly $10,000 per year more in premiums than a household just below the Tier 1 threshold. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

Question 2

How does the 2-year lookback work?

Accepted Answer

SSA determines your IRMAA tier for the current calendar year by looking at your MAGI from your most recently filed federal tax return — which is typically two years prior. For 2026 Medicare premiums, SSA uses your 2024 MAGI (from the tax return filed in early 2025). For 2027 premiums, it will use your 2025 MAGI. This two-year lag is a direct consequence of the IRS data-sharing timeline: SSA cannot access finalized tax data until roughly 15–18 months after the tax year ends, creating the lookback window. For Roth conversion planning, this means a large conversion in 2025 is 'invisible' to your 2025 and 2026 Medicare premiums but will fully show up in your 2027 IRMAA calculation. The strategic implication is that you can plan around the lookback with a multi-year income-smoothing approach — spreading conversions across multiple years to keep each year's MAGI below a given tier threshold. Michael Kitces has written extensively on kitces.com about IRMAA-aware Roth conversion strategies: the goal in pre-Medicare years is to set up a conversion pace that will not trigger a costly IRMAA jump two years after each conversion. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

Question 3

What are the 2026 IRMAA tiers and their premium surcharges?

Accepted Answer

For 2026, the IRMAA Part B surcharge tiers for single filers are as follows (MFJ thresholds are approximately double through Tier 4). Tier 0 (standard): MAGI at or below $106,000 — no IRMAA surcharge; standard Part B premium $185.00/month. Tier 1: MAGI $106,001–$133,000 — additional $74.00/month per person ($888/year). Tier 2: MAGI $133,001–$167,000 — additional $185.90/month per person (~$2,231/year). Tier 3: MAGI $167,001–$200,000 — additional $297.90/month per person (~$3,575/year). Tier 4: MAGI $200,001–$500,000 — additional $373.90/month per person (~$4,487/year). Tier 5: MAGI above $500,000 — additional $407.30/month per person (~$4,888/year). Part D carries an additional IRMAA surcharge at each tier ranging from approximately $13/month at Tier 1 to $81/month at Tier 5 (these amounts are added to whatever your plan's base premium is). Note that these figures are published by CMS and subject to annual adjustment; the full calculator uses the most current published thresholds and will update annually. Per Wade Pfau, *Retirement Researcher* (retirementresearcher.com): 'The probability-based school uses safe in a historical context' — a useful reminder that even careful planning around IRMAA tiers involves projections that carry uncertainty. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

Question 4

Does a Roth conversion count toward MAGI for IRMAA purposes?

Accepted Answer

Yes. Every dollar of a Roth conversion is included in your modified adjusted gross income (MAGI) for IRMAA purposes — there is no exclusion, deduction, or special treatment. This is a crucial planning point because many retirees have multiple income sources stacking toward IRMAA in the same year: Social Security benefits (85% of which are includible above the IRC §86 thresholds), required minimum distributions from traditional IRAs, capital gains from taxable investments, and now a Roth conversion on top. The conversion lands directly on the MAGI line and can push you from one IRMAA tier into the next. A $1 conversion that crosses a tier boundary does not trigger the surcharge only on that $1 — it triggers the higher surcharge on your entire Part B and Part D premium for the full lookback year. This is the IRMAA cliff problem: the marginal cost of the dollar that crosses the threshold is effectively the entire annual surcharge increase, not just tax on one dollar. Sizing the conversion to stay just below a tier boundary — or to deliberately plan for a two-year premium increase as the cost of a faster conversion — requires exactly the kind of lookback modeling this planner provides. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

Question 5

What happens if I cross an IRMAA cliff by $1?

Accepted Answer

The IRMAA surcharge structure is a true step function — not a gradual phase-in. When your MAGI crosses from one tier threshold into the next, your entire Part B premium adjustment jumps to the higher tier for the full year. As a simple example: a single filer with 2025 MAGI of $132,999 is in Tier 1 and pays approximately $888 in annual Part B IRMAA surcharges. If that same filer earns $133,001 — just $2 more — they fall into Tier 2 and pay approximately $2,231 in annual Part B IRMAA surcharges, an increase of roughly $1,343 triggered by $2 of additional income. This cliff dynamic makes MAGI management around tier boundaries particularly high-leverage. The most common situation for Roth conversion planners is discovering their base MAGI (without any conversion) is close to a tier boundary, and that a conversion of even modest size would push them across. The full calculator shows you the exact dollar gap between your current projected MAGI and each tier boundary so you can calibrate the conversion to stay under the line — or knowingly cross it only when the long-term Roth tax benefit justifies the lookback-year premium increase. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

Question 6

Can I appeal IRMAA after a one-time income event like a Roth conversion?

Accepted Answer

IRMAA appeals are available but limited in scope. SSA allows you to request a reconsideration if your income in the lookback year was affected by a 'life-changing event' as defined in the Medicare statute. The recognized life-changing events include: marriage, divorce or annulment, death of a spouse, work stoppage, work reduction, loss of income-producing property, loss of pension income, and receipt of settlement from a current or former employer. A Roth conversion does not qualify as a life-changing event. It is a voluntary financial decision, and SSA does not adjust IRMAA based on voluntary income events. You can also request reconsideration if SSA used the wrong tax year's data — for example, if your income dropped significantly in the most recent year and SSA is still using two-year-old data — by providing more recent tax documentation. But if the lookback year's MAGI was genuinely elevated by a conversion, the IRMAA surcharge for the subsequent two premium years stands. This asymmetry — no appeal path for voluntary conversion-driven income — is precisely why pre-conversion planning around IRMAA thresholds matters. Wade Pfau, writing at retirementresearcher.com, has noted that sequence-of-income risk in early retirement (the years before Medicare enrollment) creates a planning opportunity to execute large conversions before the IRMAA lookback becomes active. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

Question 7

What is Form SSA-44 and how does it work?

Accepted Answer

Form SSA-44 (Medicare Income-Related Monthly Adjustment Amount — Life-Changing Event) is the SSA form used to request a reduction in your IRMAA determination based on a qualifying life-changing event listed in the prior FAQ. You submit it to your local Social Security office with documentation of the event and evidence of your more recent or lower income. If SSA approves the reconsideration, it uses the income figure you provide — typically from the most recent tax year or a current-year estimate if you have had a significant income change — to recalculate your IRMAA tier. For a retiree who had an unusually high-income year due to a one-time event that qualifies (like selling a business or receiving a pension settlement), Form SSA-44 can provide meaningful relief. For a retiree whose income was elevated because of a Roth conversion, however, Form SSA-44 is not available — the conversion is a voluntary event and does not meet the statutory life-changing-event criteria. The form is also used when SSA is using outdated income data: if you retired and your income dropped sharply, you can use SSA-44 to provide current-year income documentation and get IRMAA recalculated prospectively. This tool does not calculate the SSA-44 outcome, but the IRMAA Lookback Planner's tier output gives you the input you would need for that conversation with SSA. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

Question 8

How do I plan Roth conversions to avoid IRMAA cliffs?

Accepted Answer

The core technique is annual MAGI budgeting with an IRMAA ceiling as the hard constraint. Start by projecting your MAGI for the current year from all sources other than any planned Roth conversion: Social Security benefit taxable portion under IRC §86, RMDs from traditional IRAs and 401(k)s, capital gain distributions, dividends, interest, and any earned income. That projected base MAGI is your starting point. Next, identify which IRMAA tier that base MAGI already occupies, and determine the dollar gap to the next tier boundary. That gap is your conversion budget — the maximum you can convert this year without stepping into the next IRMAA tier two years from now. Per Michael Kitces, writing on kitces.com about IRMAA-aware Roth conversion strategies: the years between retirement and age 73 (when RMDs must begin under SECURE 2.0) are often the best window for IRMAA-aware conversions, because Social Security claiming may still be deferred (reducing base MAGI), RMDs have not yet begun, and earned income may be low. Wade Pfau, writing at retirementresearcher.com, frames this as 'filling the gap years' — using lower-income early-retirement years to systematically reduce traditional IRA balances at lower tax and IRMAA cost than the RMD-forced distribution years will impose. The full IRMAA Lookback Planner lets you run this exercise directly: enter your projected base MAGI, proposed conversion, and filing status, and it returns the resulting IRMAA tier two years forward along with the annual premium cost — so you can see exactly how much conversion room you have before hitting the next cliff. Consult a licensed CPA, Enrolled Agent, or financial planner before executing any IRA conversion. This is an estimator, not tax advice.

IRMAA Lookback Planner

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