Roth Conversion Timing and IRMAA 2026: How to Convert Without Triggering Medicare Surcharges

Roth conversions are one of the most effective tax-planning moves available to pre-retirees — but they carry a hidden cost that catches many off guard: the Medicare income-related monthly adjustment amount, or IRMAA. Because a conversion adds to your taxable income, a poorly timed one can push your modified adjusted gross income (MAGI) past an IRMAA threshold and raise your Medicare premiums two years later. In 2026, those surcharges can exceed $5,800 per couple for the year. This guide shows how to time and size Roth conversions so you capture the long-term tax benefit without walking into an avoidable Medicare surcharge.

Why Roth Conversions Are Worth Doing

A Roth conversion moves money from a pre-tax traditional IRA or 401(k) into a Roth IRA. You pay ordinary income tax on the converted amount now, in exchange for tax-free growth and tax-free withdrawals later. Roth IRAs also have no lifetime required minimum distributions (RMDs), so converting reduces the future RMDs that would otherwise inflate your taxable income at 73 or 75. For retirees expecting higher tax rates later — or simply wanting to control the timing of their tax bills — conversions are a core tool to plan your retirement savings strategy.

The ideal window is often the “gap years” between retirement and the start of Social Security and RMDs, when taxable income dips and conversions can be done in lower brackets. But that same window frequently overlaps with Medicare enrollment at 65 — which is exactly where IRMAA enters the picture.

How IRMAA Works in 2026

IRMAA is a surcharge added to Medicare Part B and Part D premiums for higher-income beneficiaries. It is based on your MAGI from two years prior — so your 2026 premiums are determined by your 2024 tax return, and a conversion you do in 2026 will affect your 2028 premiums. MAGI for IRMAA is your adjusted gross income plus tax-exempt interest.

The standard 2026 Part B premium is $202.90 per month. The surcharge tiers stack on top of that. Here are the 2026 brackets:

MAGI (Single)	MAGI (Joint)	Part B Total/mo	Part D Surcharge/mo
$109,000 or less	$218,000 or less	$202.90	$0
$109,001 – $137,000	$218,001 – $274,000	$284.10	+$14.50
$137,001 – $171,000	$274,001 – $342,000	$405.90	+$37.50
$171,001 – $205,000	$342,001 – $410,000	$527.60	+$60.40
$205,001 – $500,000	$410,001 – $750,000	$649.40	+$83.30
$500,001 or more	$750,001 or more	$689.90	+$91.00

Surcharges apply per person. A married couple where both are on Medicare pays the surcharge twice.

The Cliff Problem

IRMAA is not phased in gradually. It is a cliff: cross a threshold by a single dollar and the full surcharge for that tier applies. A couple with MAGI of $274,000 pays the first-tier surcharge; at $274,001 they jump to the second tier, adding roughly $1,460 per person per year in Part B alone, plus the Part D surcharge. That is more than $3,000 of extra cost for one dollar of income. A Roth conversion that nudges you over a line can therefore carry an effective marginal cost far above your stated tax bracket.

Timing Strategies to Avoid the Surcharge

1. Convert before 65. IRMAA only applies once you are on Medicare. Aggressive conversions in your early 60s — before enrollment — never trigger a surcharge, because there are no Medicare premiums to adjust. The years from retirement to 63 are often the cleanest conversion window, since income at 63 determines premiums at 65.

2. Fill a bracket, not a cliff. Calculate how much room you have below the next IRMAA threshold and convert up to that amount, not past it. If a joint filer’s MAGI is $250,000 before conversion, there is $24,000 of room before the $274,000 cliff. Converting $20,000 stays safely under it.

3. Spread conversions over multiple years. Rather than one large conversion that blows through several tiers, a series of smaller annual conversions can keep each year under a manageable threshold while still drawing down the traditional balance before RMDs begin.

4. Mind the two-year lookback. Because IRMAA reflects income from two years prior, plan around the years that matter. A large conversion at 63 shows up at 65; one at 64 shows up at 66. Knowing the lookback lets you isolate big conversions to years where a surcharge is acceptable or unavoidable.

Appealing an IRMAA Surcharge

If a one-time event — retirement, the death of a spouse, divorce, or loss of income — caused a high-income year, you can file Form SSA-44 to request that Social Security use more recent income. A Roth conversion is not, by itself, a qualifying life-changing event, so you generally cannot appeal a surcharge caused purely by a voluntary conversion. That makes proactive planning the only real defense.

Coordinating Conversions With Physical Assets

One advantage of holding part of your retirement in physical gold or silver inside an IRA is how it interacts with this planning. Metals held in a traditional IRA still generate RMDs and, when converted, still create taxable income — so they are not a way around IRMAA. But a Roth Gold IRA, funded through carefully sized conversions, produces no future RMDs and no future taxable distributions, meaning the metals can grow without ever adding to the MAGI that drives your Medicare surcharges. For retirees who want to add physical assets to their retirement while keeping long-term taxable income low, converting metals into a Roth structure during low-income years is a strategy worth modeling.

Frequently Asked Questions

Does a Roth conversion count toward IRMAA?

Yes. A conversion adds to your modified adjusted gross income for the year, and IRMAA uses your MAGI from two years prior. A conversion in 2026 affects your 2028 Medicare premiums.

What are the 2026 IRMAA income thresholds?

Surcharges begin above $109,000 MAGI for single filers and $218,000 for joint filers, rising through tiers up to $500,000 (single) and $750,000 (joint). The standard 2026 Part B premium is $202.90.

How can I convert without triggering IRMAA?

Convert before age 65, size conversions to stay below the next threshold rather than crossing the cliff, and spread larger conversions across multiple years. Knowing the two-year lookback lets you isolate big conversions to acceptable years.

Can I appeal an IRMAA surcharge caused by a conversion?

Generally no. A voluntary Roth conversion is not a qualifying life-changing event under Form SSA-44. Appeals apply to events like retirement, loss of a spouse, or income loss — which makes upfront planning essential.

Does a Roth Gold IRA avoid IRMAA?

A Roth Gold IRA produces no RMDs and no taxable distributions, so its growth never adds to future MAGI. The conversion that funds it is taxable, but once inside the Roth, the metals do not contribute to the income that determines Medicare surcharges.