A 70-Year-Old Held Off on His Roth, Sure It Would Raise His Medicare Premium and Tax His Social Security. Qualified Withdrawals Touch Neither.

A 70-year-old retiree sits on a healthy Roth IRA and refuses to touch it. He has heard, somewhere along the way, that pulling money out will raise his Medicare premium and drag more of his Social Security into the taxable column. So the Roth sits untouched while he draws from his traditional IRA, watches his tax bill climb, and wonders whether he is being smart or just scared. Versions of this exact worry appear on retirement forums every week, usually with the same anxious phrasing: will my Roth withdrawal mess up my Medicare?

The fear is understandable. It is also backwards.

What actually counts as income, and what does not

Qualified Roth IRA withdrawals are tax-free, and the IRS does not include them in the income figures that drive either Social Security taxation or Medicare premiums. They are invisible to both formulas. That is the whole point of having paid the tax up front years ago.

“Qualified” has a specific meaning: the owner must be at least 59.5 years old and the Roth account must have been open for at least five years. A 70-year-old with a long-held Roth almost certainly clears both bars, but it is worth confirming before the first distribution.

The Social Security tax torpedo runs off provisional income, which equals adjusted gross income (AGI) plus tax-exempt interest plus half of the Social Security benefit. For single filers, once provisional income crosses $25,000, up to 50% of the benefit becomes taxable. Above $34,000, up to 85% can be taxable. For married couples filing jointly, those tiers kick in at $32,000 and $44,000. Critically, those thresholds have not been adjusted for inflation since the 1990s, which means every COLA increase quietly nudges more retirees into higher taxability territory. That 85% is the share of the benefit that can be included in taxable income, not the tax rate itself. A traditional IRA withdrawal lands inside AGI and can push more of the benefit into that zone. A qualified Roth withdrawal does not.

Medicare’s income-related monthly adjustment amount, known as IRMAA, works similarly. Part B and Part D premiums step up at modified adjusted gross income (MAGI) thresholds. For 2026, the first surcharge tier kicks in above $109,000 for single filers and $218,000 for joint filers, with the standard Part B premium of $202.90 per month rising in steps to as much as $689.90 per month at the top tier. IRMAA also works as a cliff: crossing a threshold by even $1 triggers the full surcharge for that tier. Qualified Roth withdrawals are not included in that MAGI calculation, so they cannot tip a retiree into a higher premium bracket.

The trap that catches people: conversions are not withdrawals

Here is where the confusion often starts. A qualified Roth withdrawal does not count toward income. A Roth conversion, which involves moving money from a traditional IRA into a Roth, counts as ordinary income in the year the conversion happens. That is the upfront cost of getting money into the Roth in the first place, and it is a real IRMAA and Social Security taxability event in the conversion year. Spending from an existing Roth is an entirely different transaction from funding one.

One more useful piece: under SECURE 2.0, lifetime required minimum distributions (RMDs) on Roth 401(k)s were eliminated starting in 2024. Roth IRAs already carried no lifetime RMDs for the original owner. So Roth dollars are not forced out during the owner’s life on any schedule but his own.

Where the Roth fits in the broader picture

With the 2026 cost-of-living adjustment set at 2.8%, Social Security checks rose modestly this year, and that bump itself nudges provisional income upward. Because the taxability thresholds are frozen, even a small COLA can drag more of a benefit into the taxable column. The Roth becomes a useful shock absorber against exactly that drift.

One piece of post-2025 legislation is also worth knowing. The One Big Beautiful Bill Act, signed in July 2025, created a temporary additional deduction of $6,000 per senior age 65 and older (up to $12,000 for eligible couples filing jointly) for tax years 2025 through 2028. The deduction stacks on top of the regular standard deduction and is available regardless of whether the filer itemizes. It phases out above $75,000 of income for single filers and above $150,000 for joint filers. This provision does not change the legal formula for Social Security taxability, but it can reduce taxable income enough that fewer retirees will owe federal tax on their benefits at all. That makes the Roth’s provisional-income advantage most valuable for the higher-income retirees who earn too much to benefit from the new deduction.

If a $30,000 kitchen remodel comes up, pulling the money from a traditional IRA adds $30,000 to AGI, potentially pushes more Social Security into the taxable zone, and can lift Medicare premiums into a higher tier two years later (because IRMAA is based on income from two years prior). Pulling the same $30,000 from a qualified Roth adds nothing to income, creates no taxability shift, and carries no IRMAA consequence. Same kitchen, very different tax outcome.

What to do with this

Two steps make the Roth worthwhile.

1. Confirm qualified status before the first big draw. Age 59.5 is easy at 70, but verify the five-year clock on the specific Roth account. The hardest mistake to undo is assuming qualification that does not yet exist.
2. Use the Roth where it does the most work. Reach for it in any year when an extra dollar from the traditional IRA would cross an IRMAA threshold or pull more Social Security into tax. That is the moment the Roth earns its keep.

Every retiree’s mix of accounts, filing status, and other income is different, and the thresholds that matter most depend on where the year is already landing. A quick run through the numbers with a tax preparer before a large withdrawal typically pays for itself several times over.

Editor’s note: This article was updated to include the specific provisional income thresholds that govern Social Security taxability ($25,000/$34,000 for single filers and $32,000/$44,000 for joint filers), the IRMAA cliff-system detail that a single dollar over a threshold triggers the full surcharge, the Part B premium range up to $689.90 at the top tier, and the OBBBA senior deduction of up to $6,000 per person (effective 2025 through 2028) that can reduce Social Security taxability for eligible retirees but phases out above $75,000 for single filers and $150,000 for joint filers.

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