The Medicare Surcharge That Nobody Plans Around — And the One You Should

The Medicare Surcharge That Nobody Plans Around — And the One You Should

Most retirees who think about Medicare premiums focus on the $109,000 income threshold for IRMAA — the surcharge that kicks in when modified adjusted gross income crosses a line. The anxiety is understandable. Cross the threshold by a dollar, and the full surcharge applies for the entire year, not just on the excess. For 2026, that first penalty tier adds $1,148 per person per year to Medicare Part B and Part D premiums.

But fixing your planning around that cliff is often the wrong optimization. The real planning gap — the one that costs far more than a single year of IRMAA — is the survivor's cliff. When one spouse dies, the surviving spouse loses the doubled joint-filing brackets overnight. IRMAA thresholds roughly halve. A couple comfortably below the first surcharge at $180,000 of combined income suddenly finds the survivor facing $180,000 of income against a $109,000 single-filer limit. The 22% federal tax bracket compresses from roughly $206,000 to $103,000. The standard deduction halves. And the surcharge can jump multiple tiers in one stroke.

That cliff is structural, permanent, and invisible until it triggers. Here is how to think about the full picture.

How IRMAA Actually Works

The Income-Related Monthly Adjustment Amount sits on top of standard Medicare premiums. For 2026, the base Part B premium is $202.90 per month. The Part D base is roughly $39 per month depending on your plan. If your MAGI exceeds the threshold, Medicare adds a fixed monthly surcharge to each.

The threshold for single filers in 2026 is $109,000. For married couples filing jointly, it is $218,000. These numbers are indexed to inflation annually and rise slowly — that $109,000 figure was just under $104,000 in 2025, and roughly $97,000 when the program began in 2007. They keep pace with general price increases but lag behind the income growth of many retirement portfolios.

The critical mechanism most people miss is the two-year lookback. Medicare uses your tax return from two years prior. Your 2026 premiums are determined by your 2024 tax return. A Roth conversion you execute in 2024 won't affect your Medicare bill until 2026. That lag creates both a blind spot and a planning window.

The Widow Trap

When one spouse dies, the filing status of the survivor collapses from Married Filing Jointly to Single — and the IRMAA brackets shrink with it. Consider a couple with $180,000 of MAGI filing jointly. They sit below the $218,000 threshold and pay zero surcharge. After the death of one spouse, the survivor's $180,000 of income is now measured against the $109,000 single-filer limit. That puts them at least two tiers higher, adding thousands per year in surcharges on what is actually the same income.

The problem compounds with Social Security. The surviving spouse may lose spousal benefits, which could reduce MAGI from taxable Social Security. But if the survivor is receiving a larger widow's benefit or has a large Traditional IRA generating required minimum distributions, income may stay elevated while the bracket ceiling collapses. The net effect is that the same financial life that was below the cliff for decades suddenly finds itself deep in the penalty zone.

Planning for this means modeling surviving-spouse scenarios before they happen. Roth conversions executed while both spouses are alive take advantage of the wider joint brackets and the $218,000 threshold. Each dollar converted reduces the Traditional IRA balance that will generate required minimum distributions after age 73 (or 75, depending on birth year), permanently lowering the survivor's future income stream.

The Roth Conversion Tradeoff

Here is the central tradeoff that separates good planning from good-enough planning: a Roth conversion increases your MAGI in the year you do it, potentially triggering IRMAA surcharges two years later. The conventional advice is to size conversions so you stay below the $109,000 or $218,000 threshold.

That advice is often wrong for people with large pretax balances.

For someone with a multi-hundred-thousand-dollar Traditional IRA, deferring conversions to avoid IRMAA lets the account grow tax-deferred for years. The result is a larger account feeding larger required minimum distributions at age 73 or 75, which continuously inflate MAGI and lock in higher-tier surcharges for two decades or more. Paying IRMAA briefly during a conversion phase is frequently cheaper than paying inflated-tier IRMAA on RMD-driven income for the rest of retirement.

The math is straightforward. The top IRMAA surcharge across both Part B and Part D in 2026 is $6,936 per person per year. Over a five-year conversion window, that is $34,680 in total surcharges. Now compare that to the lifetime tax savings from converting $400,000 at a marginal rate of 22% today versus paying 22% or more on those dollars as they grow inside the Traditional IRA and are forced out as RMDs. The conversion wins decisively, even with the surcharge penalty.

For smaller balances — under roughly $600,000 in pretax accounts — the calculus is different. Required minimum distributions from a $500,000 IRA start at around $13,000 to $18,000 per year, which rarely pushes anyone into a new IRMAA tier on their own. In that case, staying below the cliff during annual bracket-filling conversions may make sense because the RMD growth that drives the conversion argument simply isn't there.

What Counts as Income — And What Doesn't

IRMAA MAGI is broader than standard adjusted gross income. It includes tax-exempt interest, which means municipal bond interest that you don't pay federal tax on still counts toward your Medicare surcharge. Traditional IRA and 401(k) distributions, Roth conversions, taxable Social Security benefits, capital gains, pensions, and rental income all increase MAGI.

Equally important: qualified Roth IRA distributions, return of basis from non-qualified accounts, loans including reverse mortgages, life insurance death benefits, and HSA distributions for qualified medical expenses do not count. That list matters because it means you can restructure income without triggering the surcharge. A reverse mortgage, for instance, adds cash flow without adding MAGI. HSA distributions for medical expenses are tax-free and IRMAA-neutral. And of course, qualified Roth distributions are invisible to the Medicare calculator.

When You Can Appeal

If your income dropped significantly from the lookback year, you can file Form SSA-44 with the Social Security Administration to request recalculation using more recent income. Qualifying life-changing events include retirement, divorce, death of a spouse, work stoppage, loss of income-producing property, and employer settlement payments.

The most common use case is retirees who retired in the year before the lookback year. If you retired in 2025, your 2024 tax return — still showing full work income — will determine your 2026 premiums. Filing SSA-44 with your 2025 return documents the drop and can move you down a tier or two.

The Framework That Matters

The right question is not whether you can squeeze your MAGI below $109,000 or $218,000 this year. The right question is whether your retirement income structure minimizes lifetime taxes — including federal income tax, state tax, and Medicare surcharges — across the full span of retirement, including the survivor scenario.

IRMAA is one input in that calculation, not the calculation itself. The cliff that gets you is not the $109,000 threshold everyone warns about. It's the survivor's cliff that nobody models. And the tool that addresses both is not income minimization — it's converting pretax assets to Roth before the brackets close, before the account grows into something that generates unavoidable income, and before one spouse is no longer there to share the filing status.